ORCID Profile
0000-0002-7072-3744
Current Organisation
Flinders University
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In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Psychology | Sensory Processes, Perception and Performance | Biological Psychology (Neuropsychology, Psychopharmacology, | Sensory Processes, Perception And Performance | Biological Psychology (Neuropsychology, Psychopharmacology, Physiological Psychology) | Central Nervous System | Biochemistry and Cell Biology | Performing Arts and Creative Writing | Cell Development (Incl. Cell Division And Apoptosis) | Dance
Behaviour and Health | Disability and Functional Capacity | Nervous system and disorders | Expanding Knowledge in Psychology and Cognitive Sciences | Mental Health | Behavioural and cognitive sciences | Education policy | Expanding Knowledge through Studies of the Creative Arts and Writing | Health related to ageing | National Security |
Publisher: Elsevier BV
Date: 06-2007
DOI: 10.1016/J.BRAINRES.2007.03.036
Abstract: While patients with right parietal damage neglect the left side of stimuli, the intact-brain population shows a slight neglect of the right side--known as pseudoneglect. Although pseudoneglect occurs for physical stimuli, it is not certain whether the bias extends to mental representations. To investigate this issue, we examined spatial distortions in the representation of length for mental alphabet lines, which are thought to have a left-to-right arrangement. In Expt. 1, participants (n=10) were presented with letter strings (e.g. C_H_P) and estimated whether the letter length was greater on the left or right side of the inner-letter. The strings were presented simultaneously along a line or sequentially in the centre of the screen in either an ascending (i.e. A-Z) or descending (i.e. Z-A) sequence. Participants reliably overestimated the length on the left regardless of presentation mode. In Expt. 2, participants (n=20) judged whether the inner-letter was the true centre. Responses were biased such that inner-letters shifted to the left of true centre were perceived to be the centre. Combined, both studies demonstrate that the length on left side of the mental alphabet line is overestimated relative to the right. In Expt. 3, a reversal of the bias towards the right was found for a group of neglect patients. The data demonstrate that letters have a left-to-right mental representation and that the left side of this representation is overrepresented in a manner similar to the overestimation associated with pseudoneglect for physical stimuli.
Publisher: Duke University Press
Date: 05-2009
DOI: 10.1353/DEM.0.0053
Abstract: In recent years, a large body of research has investigated the various factors affecting child development and the consequent impact of child development on future educational and labor market outcomes. In this article, we contribute to this literature by investigating the effect of handedness on child development. This is an important issue given that around 10% of the world’s population is left-handed and given recent research demonstrating that child development strongly affects adult outcomes. Using a large, nationally representative s le of young children, we find that the probability of a child being left-handed is not significantly related to child health at birth, family composition, parental employment, or household income. We also find robust evidence that left-handed (and mixed-handed) children perform significantly worse in nearly all measures of development than right-handed children, with the relative disadvantage being larger for boys than girls. Importantly, these differentials cannot be explained by different socioeconomic characteristics of the household, parental attitudes, or investments in learning resources.
Publisher: Springer Science and Business Media LLC
Date: 13-04-2011
DOI: 10.3758/S13414-011-0117-7
Abstract: Attention is central to perception, yet a clear understanding of how attention influences the latency of perception has proven surprisingly elusive. Recent research has indicated that spatially attended stimuli are perceived earlier than unattended stimuli across a range of sensory modalities-an effect termed prior entry. However, the method commonly used to measure this, the temporal order judgment (TOJ) task, has been criticized as susceptible to response bias, despite deliberate attempts to minimize such bias. A preferred alternative is the simultaneity judgment (SJ) task. We tested the prior-entry hypothesis for somatosensory stimuli using both a TOJ task (replicating an earlier experiment) and an SJ task. Prior-entry effects were found for both, though the effect was reduced in the SJ task. Additional experiments (TOJ and SJ) using visual cues established that the earlier perception of cued tactile targets does not result from intramodal sensory interactions between tactile cues and targets.
Publisher: Elsevier BV
Date: 09-2005
DOI: 10.1016/J.COGBRAINRES.2005.04.006
Abstract: When judging the relative magnitude of the left and right sides of a stimulus, normal participants overestimate the leftward features (pseudoneglect). Although pseudoneglect and clinical neglect operate in opposite directions, the two phenomena may have a common cognitive and neural basis. For neglect, two strategies may be employed when inspecting horizontally aligned stimuli: (1) A global strategy where the stimuli are treated as a gestalt and asymmetries are detected or, (2) a comparison strategy where the qualities on the left and right sides of the stimuli are explicitly compared. To investigate the effect of these strategies on pseudoneglect, normal dextrals (n = 25 and 17) made two-alternative, forced-choice luminance discriminations between two mirror-reversed luminance gradients (greyscales). In an unseparated form, the stimuli are amenable to a global strategy. A comparison strategy was imposed by separating the stimuli into halves (Experiment 1) or quarters (Experiment 2). Despite the fact that the stimuli were equiluminant, participants predominantly chose the stimulus that was dark on the left as being darker overall in the unseparated condition. Response times were also faster for leftward responses. When the stimuli were separated into halves or quarters, the leftward bias was reduced, but not eliminated. The results demonstrate that both strategies contribute to pseudoneglect--though the global strategy may produce stronger pseudoneglect.
Publisher: Informa UK Limited
Date: 03-11-2015
Publisher: American Psychological Association (APA)
Date: 2013
DOI: 10.1037/A0030467
Abstract: We examined whether the processing of words associated with distinct spatial locations automatically biases behavior toward these locations in space. In four experiments (Ns = 30, 34, 32, 32), participants were shown stimuli denoting objects typically associated with the upper and lower regions of visual space. In Experiment 1, words were categorized as man-made or natural by pressing one of two vertically arranged keys. Reaction times were faster for trials in which response locations were congruent with the stimulus-associated locations. Experiment 2 replicated the stimulus-response congruency effect when the stimuli were presented in a pictorial format. Stimuli-space interactions therefore seem to be driven by an automatic activation of the spatial attributes associated with the stimuli, irrespective of input format. In Experiments 3 and 4, a target detection task involving only one response button was employed to examine whether the effects observed in the first two experiments were due to attentional shifts, independent of response selection processes. In both experiments, the previously observed congruence effect between words and space either diminished or vanished completely. Consequently, the results of the four experiments in the current study point to a dominant role of response-selection processes in the genesis of space-object word interactions.
Publisher: Elsevier BV
Date: 11-2009
DOI: 10.1016/J.CORTEX.2009.04.015
Abstract: Typically, numbers are spatially represented using a mental 'number line' running from left to right. In iduals with number-form synaesthesia experience numbers as occupying specific spatial coordinates that are much more complex than a typical number line. Two synaesthetes (L and B) describe experiencing the numbers 1 through 10 running vertically from bottom to top, 10-20 horizontally from left to right, 21-40 from right to left, etc. We investigated whether their number forms could bias their spatial attention using a cueing paradigm and a SNARC-type task. In both experiments, the synaesthetes' responses confirmed their synaesthetic number forms. When making odd-even judgments for the numbers 1, 2, 8, and 9, they showed SNARC-compatibility effects for up-down movements (aligned with their number form), but not left-right (misaligned) movements. We conceptually replicated these biases using a spatial cueing paradigm. Both synaesthetes showed significantly faster response times to detect targets on the bottom of the display if preceded by a low number (1, 2), and the top of the display if preceded by a high number (8, 9), whereas they showed no cueing effects when targets appeared on the left or right (misaligned with their number forms). They were however reliably faster to detect left targets following the presentation of numbers 10 and 11, and right targets following numbers 19 and 20 (since 10-20 runs from left to right). In sum, cueing and SNARC tasks can be used to empirically verify synaesthetic number forms, and show that numbers can direct spatial attention to these idiosyncratic locations.
Publisher: Elsevier BV
Date: 12-1998
Abstract: Perceptual asymmetries have been explained by structural, attentional bias and attentional advantage models. Structural models focus on asymmetries in the physical access information has to the hemispheres, whereas attentional models focus on asymmetries in the operation of attentional processes. A series of experiments was conducted to assess the contribution of attentional mechanisms to the right visual field (RVF) advantage found for word recognition. Valid, invalid and neutral peripheral cues were presented at a variety of stimulus onset asynchronies to manipulate spatial attention. Results indicated a significant RVF advantage and cueing effect. The effect of the cue was stronger for the left visual field than the RVF. This interaction supports the attentional advantage model which suggests that the left hemisphere requires less attention to process words. The attentional asymmetry is interpreted in terms of the different word processing styles used by the left and right hemispheres. These results have ramifications for the methodology used in ided visual field research and the interpretation of this research.
Publisher: Elsevier BV
Date: 05-2004
Publisher: Springer Science and Business Media LLC
Date: 17-12-2014
DOI: 10.3758/S13414-014-0813-1
Abstract: The ability to navigate accurately through the environment and avoid obstacles is essential for effective interactions with the environment. It is therefore surprising that systematic rightward errors are observed when neurologically intact participants navigate through doorways-most likely due to the operation of biases in spatial attention. These rightward errors may arise due to the operation of an extinction-like process, whereby participants overattend to the left doorpost and collide with the right one. Alternatively, rightward biases might reflect a bisection bias, such that the extrapersonal nature of the aperture causes participants to misbisect the aperture slightly to the right of true center. Because eye movements and spatial attention are closely related, in this study we used eyetracking to test the extinction and bisection models in a remote wheelchair navigation task. University students (n = 16) made rightward errors when navigating the wheelchair through a doorway, and fixated more frequently toward the right side of the aperture throughout the trial. These results are inconsistent with an extinction-based theory of navigation asymmetry, which predicts a leftward bias in eye position due to participants overattending to the left side of the doorway. Instead, the observed rightward bias in eye movements strongly supports a bisection-based theory of navigation asymmetry, whereby participants mentally "mark" the midpoint of a doorway toward the right and then head toward that point, resulting in rightward deviations. The rightward nature of participants' navigation errors and eye positions is consistent with the existence of a rightward attentional bias for extrapersonal stimuli.
Publisher: Informa UK Limited
Date: 25-07-2015
DOI: 10.1080/02699931.2015.1053842
Abstract: Approach motivation leads to greater left hemisphere activation, whereas an avoidant motivational state activates the right hemisphere. Recent research, which served as the basis for the current experiment, suggests line bisection provides a simple measure of approach/avoidance lateralisation. Findings from Experiment 1 indicated that the landmark task was sensitive enough to identify lateral asymmetries evoked by happy and angry faces however, follow-up experiments failed to replicate this finding. When task instructions were slightly modified or when a mixed design was used, motivation did not influence landmark task performance. The use of images in lieu of faces also failed to produce a significant effect. Importantly, a straight replication of Experiment 1 produced a null result. Line bisection does not appear to be a suitable measure of lateralised approach/avoidance biases, possibly due to the high in idual variability inherent in visuospatial biases. Implications for null hypothesis significance testing are also discussed.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-2012
Publisher: Frontiers Media SA
Date: 2012
Publisher: Wiley
Date: 11-2010
Publisher: Springer Science and Business Media LLC
Date: 24-04-2015
Publisher: Springer Science and Business Media LLC
Date: 17-11-2011
DOI: 10.1007/S11065-011-9184-8
Abstract: Body integrity identity disorder (BIID) is characterised by profound experience of incongruity between the biological and desired body structure. The condition manifests in "non-belonging" of body parts, and the subsequent desire to utate, paralyse or disable a limb. Little is known about BIID however, a neuropsychological model implicating right fronto-parietal and insular networks is emerging, with potential disruption to body representation. We argue that, as there is scant systematic research on BIID published to date and much of the research is methodologically weak, it is premature to assume that the only process underlying bodily experience that is compromised is body representation. The present review systematically investigates which aspects of neurological processing of the body, and sense of self, may be compromised in BIID. We argue that the disorder most likely reflects dysregulation in multiple levels of body processing. That is, the disunity between self and the body could arguably come about through congenital and/or developmental disruption of body representations, which, together with altered multisensory integration, may preclude the experience of self-attribution and embodiment of affected body parts. Ulimately, there is a need for official diagnostic criteria to facilitate epidemiological characterisation of BIID, and for further research to systematically investigate which aspects of body representation and processing are truly compromised in the disorder.
Publisher: Elsevier BV
Date: 08-2011
DOI: 10.1016/J.BANDC.2011.04.006
Abstract: Distinct cognitive and neural mechanisms underlie perception and action in near (within-reach) and far (outside-reach) space. Objects in far space can be brought into the brain's near-space through tool-use. We determined whether a near object can be pushed into far space by changing the pictorial context in which it occurs. Participants (n = 372) made relative length judgements for lines presented in near space, but superimposed over photographs of near and far objects. The left segment of the line was overestimated in the baseline and near-context conditions whereas the right was overestimated in the far-context. The change from leftward to rightward overestimation is the same when lines are physically shifted from near to far space. Because participants did not have to do anything in relation to the photograph, the results suggest that simply viewing images with a near/far context can cause a shift of attention along the distal roximal axis, which may reflect differential activation of the ventral/dorsal visual streams.
Publisher: Springer Science and Business Media LLC
Date: 26-07-2016
DOI: 10.1007/S00221-016-4735-0
Abstract: When iding attention between the left and right sides of physical space, most in iduals pay slightly more attention to the left side. This phenomenon, known as pseudoneglect, may also occur for the left and right sides of mental representations of stimuli. Representational pseudoneglect has been shown for the recall of real-world scenes and for simple, briefly presented stimuli. The current study sought to investigate the effect of exposure duration and complexity using adaptations of the Rey-Osterrieth figures. Undergraduates (n = 97) were shown a stimulus for 20 s and asked to remember it. Participants were then shown a probe and indicated whether it was the same or different. Results showed that, irrespective of whether an element was added or subtracted, changes on the left side of the remembered image were better detected. These results are consistent with representational pseudoneglect and demonstrate that this effect occurs for complex stimuli when presented for an extended period of time. Representation neglect is therefore unlikely to be the result of an initial saccade to the left-but could be related to the formation or recall of the representation.
Publisher: Informa UK Limited
Date: 12-07-2018
Publisher: Oxford University Press (OUP)
Date: 22-10-2012
DOI: 10.1111/J.1467-985X.2012.01074.X
Abstract: Using data from the child supplement of the US National Longitudinal Survey of Youth, and fitting three-level random-effects models of child health and cognitive development, we test whether left-handed children have different outcomes from those of their right-handed counterparts. The health measures cover both physical health and mental health, and the cognitive development test scores span vocabulary, mathematics, reading and comprehension. Overall we find little evidence to suggest that left-handed children have a significantly higher probability of experiencing injury, illness or behavioural problems. In contrast, we find that left-handed children have significantly lower cognitive development test scores than right-handed children for all areas of development with the exception of reading. Moreover, we find no strong evidence that the left-handedness effect differs by gender or age.
Publisher: Elsevier BV
Date: 10-2015
DOI: 10.1016/J.BANDC.2015.08.005
Abstract: Our ability to process information about an object's location in depth varies along the horizontal and vertical axes. These variations reflect functional specialisation of the cerebral hemispheres as well as the ventral/dorsal visual streams for processing stimuli located in near and far space. Prior research has demonstrated visual field superiorities for processing near space in the lower and right hemispaces and for far space in the upper and left hemispaces. No research, however, has directly tested whether the functional specialisation of the visual fields actually makes objects look closer when presented in the lower or right visual fields. To measure biases in the perception of depth, we employed anaglyph stimuli where participants made closer/further judgments about the relative location of two spheres in a three-dimensional virtual space. We observed clear processing differences in this task where participants perceived the right and lower spheres to be closer and the left and upper spheres to be further away. Furthermore, no relationship between the horizontal and vertical dimensions was observed suggesting separate cognitive/neural mechanisms. Not only does this methodology clearly demonstrate differences in perceived depth across the visual field, it also opens up many possibilities for studying functional asymmetries in three-dimensional space.
Publisher: Informa UK Limited
Date: 2006
DOI: 10.1080/13576500701751287
Abstract: Relative finger length can predict a person's gender or their hand preference. We measured finger length using a new "tubes" test, which required participants to slide a clear plastic tube over their fingers and read the length from an attached mm scale. Data collected from 600 students demonstrated that the right fingers are longer than the left for dextrals, but not for non-dextrals. Examination of the relative length of the index and ring fingers revealed a clear gender effect. There was also an effect of hand preference on index/ring finger ratio whereby non-dextrals showed a more masculine pattern compared to dextrals. For non-dextrals, prenatal exposure to high testosterone levels may have caused both a shift away from dextrality and a more masculine pattern of finger ratio. In the second experiment, finger length was measured by the tubes test and by photocopying the hands in 124 undergraduates. The tubes test yielded a longer estimate of ring finger length compared to the photocopy method. Despite this, there was a strong correlation between the tests and both showed an association with gender. Finally, test-retest scores for 45 participants showed a high level of reliability for absolute and relative finger measures. We conclude that the tubes technique provides an effective and easy-to-use means of measuring finger length, which can be administered in a classroom setting.
Publisher: Elsevier BV
Date: 03-2010
Publisher: Springer Science and Business Media LLC
Date: 25-11-2010
DOI: 10.1007/S00426-010-0315-2
Abstract: This study explored the mechanisms that underlie asymmetries for the horizontal vertical illusion (HVI), which deceives length perception, so that a vertical line is perceived as longer than a horizontal line of equivalent length. In Experiment 1, university students (n = 14) made length judgements for vertical and horizontal lines. The vertical line was shifted in eight steps from the far left of the horizontal line (⌊) to the far right (⌋). An HVI was observed for the medial positions (⊥), which diminished towards the lateral positions. The HVI was also stronger when the vertical line was on the left. Because the left/right asymmetry changed as a function of lateral/medial position, the asymmetry within the HVI stimulus is most likely the result of pseudoneglect, which affects judgements of horizontal length. In Experiment 2, participants (n = 15) made judgements for HVI stimuli presented to the left- and right-hemispace and the midline. The HVI was stronger in the left hemispace. Because the asymmetry between the left- and right-hemispaces did not interact with the asymmetry within the stimuli, it was concluded that the asymmetry between hemispatial positions was the result of right hemisphere susceptibility to illusory geometrical effects whereas the asymmetry within the stimulus is related to an object-centred attentional asymmetry. The HVI is affected by asymmetries in length judgements and susceptibility to illusions and may provide interesting insights into attentional disorders in clinical populations, such as neglect.
Publisher: Informa UK Limited
Date: 2010
Publisher: Public Library of Science (PLoS)
Date: 02-05-2012
Publisher: Elsevier BV
Date: 04-2015
DOI: 10.1016/J.NEUROPSYCHOLOGIA.2014.10.008
Abstract: Being in close social proximity to a stranger is generally perceived to be an uncomfortable experience, which most people seek to avoid. In circumstances where crowding is unavoidable, however, people may seek to withdraw their attention from the other person. This study examined whether social discomfort, as indexed by electrodermal activity, is related to a withdrawal of attention in 28 (m=8, f=20) university students. Students performed a radial line bisection task while alone or together with a stranger facing them. Physiological arousal was indexed by a wrist monitor, which recorded electrodermal activity. Correlational analyses showed that in iduals who displayed physiological discomfort when together showed a withdrawal of the perceived midpoint of the line towards them (and away from the stranger). Conversely, in iduals who showed no discomfort exhibited an expansion of the perceived midpoint away from them. We propose that participants shift their attention away from the stranger to increase interpersonal distance and reduce anxiety/arousal.
Publisher: Springer Science and Business Media LLC
Date: 05-2009
DOI: 10.3758/APP.71.4.847
Publisher: Elsevier BV
Date: 12-2017
DOI: 10.1016/J.BODYIM.2017.09.004
Abstract: Although there is a growing consensus that women with anorexia nervosa have a distorted body schema, the origins of this disturbance remain uncertain. The present investigation examined the effects of body size, eating pathology, and sex upon the body schema of an at-risk, undergraduate population. In Study 1, 98 participants mentally simulated their passage through apertures. When aperture width was manipulated, narrow and broad women over- and under-estimated their spatial requirements for passage, respectively. This relationship was exacerbated by dietary restraint. When aperture height was manipulated, short and tall men over- and under-estimated their spatial requirements for passage, respectively. Study 2 (N=32) replicated the association between women's veridical and internally-represented widths, although no significant effects of eating pathology were observed. Our findings suggest that body schema enlargement is not necessarily pathological, and may be driven by normal perceptual biases and internalised sociocultural body ideals.
Publisher: SAGE Publications
Date: 12-2013
DOI: 10.1080/17470218.2013.863371
Abstract: Null hypothesis significance testing uses the seemingly arbitrary probability of .05 as a means of objectively determining whether a tested effect is reliable. Within recent psychological articles, research has found an overrepresentation of p values around this cut-off. The present study examined whether this overrepresentation is a product of recent pressure to publish or whether it has existed throughout psychological research. Articles published in 1965 and 2005 from two prominent psychology journals were examined. Like previous research, the frequency of p values at and just below .05 was greater than expected compared to p frequencies in other ranges. While this overrepresentation was found for values published in both 1965 and 2005, it was much greater in 2005. Additionally, p values close to but over .05 were more likely to be rounded down to, or incorrectly reported as, significant in 2005 than in 1965. Modern statistical software and an increased pressure to publish may explain this pattern. The problem may be alleviated by reduced reliance on p values and increased reporting of confidence intervals and effect sizes.
Publisher: Springer Science and Business Media LLC
Date: 23-08-2018
DOI: 10.1038/S41598-018-31129-7
Abstract: Although the perception of faces depends on low-level neuronal processes, it is also affected by high-level social processes. Faces from a social in-group, such as people of a similar age, receive more in-depth processing and are processed holistically. To explore whether own-age biases affect subconscious face perception, we presented participants with the young/old lady ambiguous figure. Mechanical Turk was used to s le participants of varying ages from the USA. Results demonstrated that younger and older participants estimated the age of the image as younger and older, respectively. This own-age effect ties in with socio-cultural practices, which are less inclusive towards the elderly. Participants were not aware the study was related to ageing and the stimulus was shown briefly. The results therefore demonstrate that high-level social group processes have a subconscious effect on the early stages of face processing. A neural feedback model is used to explain this interaction.
Publisher: American Psychological Association (APA)
Date: 06-2016
DOI: 10.1037/XAP0000078
Abstract: Our ability to attend to the environment is asymmetrical and affects activities like navigation. This study investigated whether rightward deviations exist for miniaturized vehicles. Experiment 1 asked participants (n = 26) to navigate a remote-controlled car through apertures that were 200, 300 or 400 mm wide. Analyses revealed a nonsignificant trend for the rightward deviation to increase with aperture width. None of the deviations was significantly to the right. Experiment 2 (n = 16) elevated the car to eye level to control for upper/lower visual-field effects. The results were unchanged. Experiment 3 (n = 16) altered the car's mechanical drive to control veering effects, and the results were unchanged. Data from Experiments 1-3 were combined to increase statistical power and showed that the rightward deviation increased for wider apertures. Experiment 4 (n = 17) investigated deviations for wider apertures (1,100 mm) and found a rightward deviation. Finally, Experiment 5 (n = 24) used a different type of remote-controlled vehicle. A rightward deviation, which increased with width, was observed. In addition, the degree of rightward deviation was related to the perceived middle of the aperture. It appears that systematic rightward deviations occur for miniaturized vehicles, which increase with aperture width. The implications of these results for attentional explanations of rightward deviation are discussed. (PsycINFO Database Record
Publisher: Springer Science and Business Media LLC
Date: 23-08-2000
Abstract: Inhibition of return' (IOR) refers to the delayed detection often found for targets at the same location as a preceding event. We examined whether IOR reflects a truly supramodal phenomenon, in an experiment designed to avoid criticisms of previous crossmodal research. We presented a random sequence of visual, tactile, and auditory targets to either the left or right of central fixation, and tested for IOR between targets in all three modalities when presented successively to the same versus different side. Speeded detection for targets in all three modalities was indeed slower if the preceding target had been presented from the same position, regardless of the modality, of this preceding target. These results demonstrate for the first time that IOR is truly supramodal.
Publisher: Elsevier BV
Date: 06-2008
DOI: 10.1016/J.COGNITION.2007.09.007
Abstract: Adaptation to right-shifting prisms improves left neglect for mental number line bisection. This study examined whether adaptation affects the mental number line in normal participants. Thirty-six participants completed a mental number line task before and after adaptation to either: left-shifting prisms, right-shifting prisms or control spectacles that did not shift the visual scene. Participants viewed number triplets (e.g. 16, 36, 55) and determined whether the numerical distance was greater on the left or right side of the inner number. Participants demonstrated a leftward bias (i.e. overestimated the length occupied by numbers located on the left side of the number line) that was consistent with the effect of pseudoneglect. The leftward bias was corrected by a short period of visuomotor adaptation to left-shifting prisms, but remained unaffected by adaptation to right-shifting prisms and control spectacles. The findings demonstrate that a simple visuomotor task alters the representation of space on the mental number line in normal participants.
Publisher: Elsevier BV
Date: 11-2012
DOI: 10.1016/J.CORTEX.2011.10.003
Abstract: To explore the idea of a perceptual distortion of space in spatial neglect, neglect patients, age-matched healthy controls and right hemisphere control patients judged the vanishing point of horizontally and vertically-moving stimuli. Hemifield of presentation and movement direction of the stimulus presentation was manipulated. The results suggest that neglect patients show a stronger response bias in the direction of the moving stimuli ("representational momentum") than healthy and right hemisphere controls. Furthermore, neglect patients, but not the control groups, showed a direction-specific response whereby the presence of neglect was associated with a larger representational momentum for leftward-moving stimuli. The one left-hemisphere patient with right-sided neglect showed the opposite effect. Thus, neglect patients showed a relative overextension into their neglected side of space. While these findings are in line with the idea of an extension in the representation of contralesional space, other explanations such as deficient spatial remapping, impairments in smooth pursuit and distortions in memorized visuo-motor movements are considered.
Publisher: Elsevier BV
Date: 03-1999
DOI: 10.1016/S0028-3932(98)00074-8
Abstract: Perceptual asymmetries under free-viewing conditions were investigated in 24 normal dextral adults. Three tasks were administered that required participants to chose between a pair of left/right reversed stimuli on the basis of their brightness, numerosity or size. These stimulus features were represented asymmetrically within the stimuli, so that each stimulus appeared darker, larger or more numerous on the left or right sides. Participants more often selected the stimulus with the relevant feature on the left-hand side for all three tasks. Response times for leftward responses were faster than rightward responses. Split-half reliabilities revealed a high level of consistency within the tasks. However, the correlation between tasks was low. These results suggest that the different tasks, while showing similar levels of perceptual asymmetry, engage distinct sets of lateralised processes.
Publisher: No publisher found
Date: 2000
Publisher: Elsevier BV
Date: 11-1993
DOI: 10.1016/0028-3932(93)90066-9
Abstract: Two thematic versions of an inspection time task were administered to 18 normal, right-handed subjects. For both tasks, subjects were required to make a categorical discrimination related to the length of two lines. In one version of the task (time task), difficulty was manipulated by varying the exposure duration of the lines. In the other version (length task), difficulty was manipulated by varying the degree to which one line was shorter than the other. The time task was designed to measure the temporal acuity of the observer while the length task was used to gauge subjects' capacity for the same categorical discrimination independent of temporal acuity. Thus, the two tasks were designed to dissociate the categorical and temporal aspects of the inspection time task. Divided visual field techniques revealed a significant left hemisphere (LH) advantage for the time task, but no asymmetry for the length task. These results could not be accounted for in terms of the categorical nature of the representation. A model, related to the LH's predisposition for the detection of fine temporal events provided a more satisfactory account of the results.
Publisher: Public Library of Science (PLoS)
Date: 17-07-2012
Publisher: Springer Science and Business Media LLC
Date: 08-2010
Publisher: Elsevier BV
Date: 11-2008
DOI: 10.1016/J.BANDC.2008.04.003
Abstract: Whereas right parietal damage can result in left hemineglect, the general population shows a subtle neglect of the right hemispace-known as pseudoneglect. A recent study has demonstrated that people collide to the right more often and attributed this bias to pseudoneglect. [Nicholls, M. E. R., Loftus, A., Meyer, K., & Mattingley, J.B. (2007). Things that go bump in the right: The effect of unimanual activity on rightward collisions. Neuropsychologia, 45, 1122-1126]. Nicholls examined the effect of unimanual activation by requiring participants to fire projectiles at a target whilst walking and found that the rightward bias was exaggerated or reversed when the left and right hands were active, respectively. However, the act of aiming at a target may have inadvertently biased walking trajectory to the right. The current study addressed this issue by requiring participants (n=149) to walk through a narrow doorway three times whilst entering text into a phone using the (a) left, (b) right or (c) both hands. Despite the fact that entering text into a phone should produce no rightward bias, participants bumped to the right more often. Unlike previous research, no effect of unimanual activation was observed. This lack of effect was attributed to the smaller hand movements for entering numbers compared to firing a toy gun. Finally, this study showed an association for the first time between biases in observable bumping and line bisection performance-suggesting that unilateral bumping is related to pseudoneglect.
Publisher: Springer Science and Business Media LLC
Date: 21-06-2014
DOI: 10.1007/S00221-014-4015-9
Abstract: Neurologically normal in iduals devote more attention to the left side an asymmetry known as pseudoneglect, which reflects right hemisphere involvement in visuospatial attention. The role of eye movements in attentional asymmetries has received little consideration, particularly in terms of the greyscales task. Stimulus length, elevation, and presentation duration were manipulated, while monitoring eye movements during the greyscales task. Region of interest analyses compared time spent examining each quadrant of the stimulus. Further, saccades were examined in conjunction with fixations to gain an understanding of overall eye movement patterns. Scatterplots combining x-and y-coordinates illustrate mean eye position. Results demonstrated a comparison strategy was used, where the dark portions of each rectangle were fixated. Mean eye position was within the lower left quadrant. The left visual field was inspected most for the baseline condition. Interestingly, the lower visual field was examined most when duration, length, or elevation was manipulated. Eye movement patterns provide a possible explanation for why correlations are y not observed between visuospatial tasks. Different strategies, based on specific-task demands, are likely to be used, which in turn, engage separate aspects of visuospatial attention.
Publisher: Informa UK Limited
Date: 03-03-2017
Publisher: Informa UK Limited
Date: 11-2005
DOI: 10.1080/13576500442000265
Abstract: Schizophrenia and schizotypal personality have been linked to sinistrality as well as ambidextrality. The current study clarifies the relation between laterality and schizotypal personality by administering a battery of laterality questionnaires to measure hand, eye, ear, and foot preference in a group of 933 university students. To determine whether the relationship between schizotypy and laterality is limited to self-report measures, performance asymmetries between the hands were measured with tapping rate. There was no difference between dextrals and sinistrals in schizotypal personality, as indexed by the Magical Ideation (MI) scale. MI was higher, however, for in iduals with a weak preference for either hand or eye compared to those with a strong dominance. In addition, in iduals inconsistent in their lateral preference across modalities showed higher MI scores. Performance asymmetries had no effect on MI scores. This lack of effect was attributed to the inability of performance measures, such as tapping rate, to identify ambidextrals. The results support research linking schizotypal personality to ambidextrality and weak cerebral dominance and demonstrate that the association extends to modalities other than hand preference.
Publisher: American Psychological Association (APA)
Date: 07-2000
Publisher: Elsevier BV
Date: 1991
DOI: 10.1016/0028-3932(91)90101-D
Abstract: An inspection time task, used to gauge differences in speed of information processing between the hemispheres, was administered to 22 normal subjects. It was found that the left visual field-right hemisphere (LVF-RH) exhibited an inferior performance relative to the right visual field-left hemisphere (RVF-LH). These results were consistent with other studies which have found an RVF-LH advantage for the processing of temporal/serial information. The possible ramifications of these results for models of asymmetry which do and do not attribute the left hemisphere's preferential capacity for language to these fundamental processes are then discussed.
Publisher: Springer Science and Business Media LLC
Date: 09-03-2011
DOI: 10.3758/S13414-011-0114-X
Abstract: Time, number, and space may be represented in the brain by a common set of cognitive/neural mechanisms. In support of this conjecture, Schwarz and Eiselt (Journal of Experimental Psychology: Human Perception and Performance, 35, 989-1004, 2009) found that numerically smaller digits were perceived to occur earlier than larger digits, and they concluded that this difference reflected faster processing of smaller numbers. This difference, however, could have been related to a response bias, whereby participants map responses of "which first" onto the "first" number along the mental number line. In Experiment 1, participants made temporal order judgements between digits presented to the left or to the right. The point of subjective simultaneity was shifted so that the 9 had to be presented before the 2 in order for simultaneity to be perceived. This difference could reflect either faster processing of the 2 or a response bias. Experiments 2a and 2b eliminated response biases by using simultaneity judgements, which have no logical stimulus mapping. Both of the latter experiments established that the 2 was not processed faster than the 9. Although the present results relate specifically to numerical magnitude and temporal order associations, they also have broader implications. Other studies have reported associations between dimensions such as size, duration, and number and have attributed these to parietal mechanisms. Such associations, however, may also be an artefact of response biases.
Publisher: Elsevier BV
Date: 2007
DOI: 10.1016/J.NEUROPSYCHOLOGIA.2006.07.015
Abstract: Patients with right parietal damage and spatial neglect ignore the leftward features of their environment - causing them to bump into the left-side of doorways. In contrast, the normal population shows a mild attentional bias towards the left. Self-report measures show more collisions to the right in everyday settings. We sought to obtain a quantitative measure of lateralised bumping in a laboratory setting. Participants (n=276) walked through a narrow doorway and the experimenter recorded collisions. To investigate the association between bumping and paper-and-pencil tests of pseudoneglect, a line bisection task was administered. Unilateral activation of the hemispheres has been found to ameliorate the effects of spatial neglect. We investigated the effect of activation by asking participants to move their left-, right- or both-hands as they walked. In the both hands condition, which acted as a baseline, there were more right bumps than left bumps. The rightward bias was exasperated when the left hand moved, presumably because this movement activated the right hemisphere. In contrast, there were more left bumps when the right hand moved. The results demonstrate that bumping is not random and that we collide with the right side more often. Biases in bumping, however, were not related to biases in line bisection. The effect of hand-movement demonstrates that bumping is brought about by an imbalance of activation between the hemispheres.
Publisher: Springer Science and Business Media LLC
Date: 18-01-2006
DOI: 10.1007/S00221-005-0303-8
Abstract: Under free-viewing conditions, the leftward stimulus features are frequently overestimated (pseudoneglect). This asymmetry could reflect the operation of: (a) spatial attention mechanisms in the right hemisphere (RH) or, (b) stimulus-specific activation. To test these propositions, we attempted to induce a stimulus-specific dissociation between the hemispheres under free-viewing conditions. In two experiments (n=23, n=22) dextrals carried out two tasks. The 'grayscales' task required luminance judgments between two mirror-reversed luminance gradients. The flicker task required temporal frequency judgments between two mirror-reversed temporal gradients. The grayscales and flicker tasks suited the processing styles of the right and left hemispheres, respectively. For both experiments, a strong leftward bias was observed for the grayscales task, which could be the result of both of the mechanisms outlined above. In Experiment 1, there was a rightward bias for the flicker task-but only for participants with longer reaction times. In Experiment 2, where all responses were delayed, a rightward bias was found for the flicker task for shorter stimuli. The data demonstrate that stimulus-specific dissociations can be induced under free-viewing conditions. However, the fact that the rightward bias was: (a) weaker than the leftward bias and, (b) reduced by increases in length, demonstrates that RH spatial attention mechanisms are also important.
Publisher: Wiley
Date: 08-2011
DOI: 10.1016/J.EJPAIN.2011.01.005
Abstract: Phantom phenomena are frequent following utation, but how this often painful experience is modified or triggered by spontaneous events or sensations often puzzles utees and clinicians alike. We explored triggers of phantom phenomena in a heterogeneous s le of 264 upper and lower limb adult utees with phantom sensations. Participants completed a structured questionnaire to determine the prevalence and nature of the triggers of phantom phenomena. The four categories of triggers identified include: (a) a quarter of participants experiencing psychological, emotional or autonomic triggers (b) half experiencing behavioral triggers, "forgetting" the limb's absence and attempting to use the phantom (c) one-fifth experiencing weather-induced triggers and (d) one-third experiencing sensations referred from parts of the body. Upper limb utees and were more likely to experience weather-induced phantom phenomena than lower limb utees and upper and lower limb utees were equally likely to experience referred sensations from the genitals, contradicting the homuncular remapping hypothesis. Traumatic utees were more likely to report emotional triggers. Further, while those with emotional triggers exhibited poorer acceptance of the limitations of utation, they were more likely to employ adaptive coping mechanisms. Finally, habitual "forgetting" behaviors were most common soon after utation, whereas other more adaptive schemata (e.g., self-defense) were equally likely to be performed at any time following utation. Various likely inter-related mechanisms are discussed in relation to phantom triggers. Ultimately, optimizing stump and neuroma management, as well as restoring function of central networks for pain, limb movement, and utation-related memories, should help manage spontaneously triggered phantom phenomena.
Publisher: SAGE Publications
Date: 05-2009
DOI: 10.1080/17470210802305318
Abstract: Patients with unilateral neglect of the left side bisect physical lines to the right whereas in iduals with an intact brain bisect lines slightly to the left (pseudoneglect). Similarly, for mental number lines, which are arranged in a left-to-right ascending sequence, neglect patients bisect to the right. This study determined whether in iduals with an intact brain show pseudoneglect for mental number lines. In Experiment 1, participants were presented with visual number triplets (e.g., 16, 36, 55) and determined whether the numerical distance was greater on the left or right side of the inner number. Despite changing the spatial configuration of the stimuli, or their temporal order, the numerical length on the left was consistently overestimated. The fact that the bias was unaffected by physical stimulus changes demonstrates that the bias is based on a mental representation. The leftward bias was also observed for sets of negative numbers (Experiment 2)—demonstrating not only that the number line extends into negative space but also that the bias is not the result of an arithmetic distortion caused by logarithmic scaling. The leftward bias could be caused by a rounding-down effect. Using numbers that were prone to large or small rounding-down errors, Experiment 3 showed no effect of rounding down. The task demands were changed in Experiment 4 so that participants determined whether the inner number was the true arithmetic centre or not. Participants mistook inner numbers shifted to the left to be the true numerical centre—reflecting leftward overestimation. The task was applied to 3 patients with right parietal damage with severe, moderate, or no spatial neglect (Experiment 5). A rightward bias was observed, which depended on the severity of neglect symptoms. Together, the data demonstrate a reliable and robust leftward bias for mental number line bisection, which reverses in clinical neglect. The bias mirrors pseudoneglect for physical lines and most likely reflects an expansion of the space occupied by lower numbers on the left side of the line and a contraction of space for higher numbers located on the right.
Publisher: Springer Science and Business Media LLC
Date: 04-2008
DOI: 10.3758/PBR.15.2.413
Abstract: The mental representation of numbers along a line oriented left to right affects spatial cognition, facilitating responses in the ipsilateral hemispace (the spatial-numerical association of response codes [SNARC] effect). We investigated whether the number/space association is the result of an attentional shift or response selection. Previous research has often introduced covert left/right response cues by presenting targets to the left or the right. The present study avoided left/right cues by requiring forced choice upper/lower luminance discriminations to two mirror-reversed luminance gradients (the grayscale task). The grayscale stimuli were overlaid with strings of (1) low numbers, (2) high numbers, and (3) nonnumerical characters. In Experiment 1, 20 dextrals judged the number's magnitude and then indicated whether the upper/lower grayscale was darker. Results showed leftward and rightward attentional biases for low and high numbers, respectively. Demands to process numbers along a left/right line were made less explicit in Experiment 2 (N = 18 dextrals), using (1) a parity judgment and (2) arbitrary linguistic labels for top/bottom. Once again, a spatial congruency effect was observed. Because the response (up/down) was orthogonal to the dimension of interest (left/right), the effect of number cannot be attributed to late-stage response congruencies. This study required unspeeded responses to stimuli presented in free vision, whereas other experiments have used speeded responses. Understanding the time course of number-space effects may, therefore, be important to the debate associated with response selection.
Publisher: Elsevier BV
Date: 05-2010
DOI: 10.1016/J.CORTEX.2009.06.010
Abstract: Spatial neglect can be characterized by a "magnetic attraction" towards the right side of a visual stimulus array and a selection of stimuli from that hemispace. This study examined whether these distinctive characteristics in visuo-motor space are also evident in representational number space. Given that numbers are thought to be represented along a left-to-right oriented mental number line, an affinity for the spontaneous selection of larger numbers was anticipated for neglect patients. Contrary to this expectation, neglect patients (n=20) picked a similar range of numbers compared to controls (n=17) when generating a number between 1000 and 10,000 and when playing an imaginary lottery game. There was, however, a positive correlation between the biases for the imaginary lottery, number generation and a number bisection task - demonstrating that exploration asymmetries along the mental number line are consistent within in iduals across tasks. Some of the patients selected smaller numbers in all of these tasks, confirming reports of dissociations between physical and numerical-representational forms of neglect. Conversely, only four (20%) of the patients could reliably be classified as demonstrating a neglect in number space. When filling out a physical lottery ticket, the neglect patients showed the expected bias towards picking numbers placed on the right-hand side of the ticket. These results demonstrate that the magnetic attraction towards the right side of mental representations is rather weak and that representational forms of neglect only occasionally co-exist with neglect in physical space.
Publisher: Informa UK Limited
Date: 26-03-2014
DOI: 10.1080/00140139.2014.899633
Abstract: Attention can be captured by distractors and can affect performance. To examine whether asymmetrical distractors, such as a wall, affect spatial attention, Experiment 1 required participants (n = 20) to determine the relative length of pre-bisected lines when a temporary barrier was placed close to the left or right sides of the display. Post-hoc tests showed that attention was drawn towards left, but not right, walls. Experiment 2 (n = 18) sought to increase this effect using a solid brick wall rather than a temporary barrier. Instead of strengthening the result, no effect of barrier was observed. A non-effect was also observed in Experiment 3 (n = 18) when participants moved a cursor to the line's middle. Finally, Experiment 4 (n = 26) showed that asymmetrical barriers had no effect on visual search. While the data showed some evidence that attention is distracted by walls placed to the left, this effect is weak and task-specific. The ability to monitor critical information on displays can be affected by asymmetrical distractors. In many workplaces, a display may be placed alongside a wall. This study explored whether a wall placed to the left/right affects spatial attention. A weak, task-specific, attraction effect was observed for walls on the left.
Publisher: Informa UK Limited
Date: 08-1998
DOI: 10.1076/JCEN.20.4.445.1474
Abstract: Hemispheric asymmetries for tactile temporal discriminations were examined in 29 dextrals. Vibrations lasting 120 ms were delivered unilaterally to the hands, half of which contained a gap lasting between 6 and 18 ms. Participants indicated whether or not the vibration contained a gap. Visual and auditory research has demonstrated a left hemisphere (LH) advantage for gap detection. However, this research has confounded the effects of hemisphere and hemispace. These effects were dissociated using midline and lateral hand placements. Reaction time (p < .05), response error (p < .1), and response bias (p < .05) measures revealed a LH advantage for gap detection. The asymmetry was reduced in the midline condition for the error data only (p < .1). These results demonstrate that the LH is better able to detect brief temporal events than is the right hemisphere. Hemispace appears to have a limited impact on this asymmetry.
Publisher: Elsevier BV
Date: 09-2011
Publisher: Informa UK Limited
Date: 2009
Publisher: Informa UK Limited
Date: 27-04-2021
Publisher: Elsevier BV
Date: 02-1994
DOI: 10.1016/0028-3932(94)90006-X
Abstract: Divided visual field techniques were used to investigate hemispheric asymmetries for the threshold of fusion of two flashes in a group of right-handed adults. A right visual field (RVF) advantage was found and this was interpreted in terms of the left hemisphere's enhanced capacity for the detection of fine temporal events. This asymmetry could be the result of either (a) a structural advantage (where an asymmetry in physical access exists) or (b) an attentional bias (where attention is biased to one side). In order to assess the contribution of attentional and structural factors, attention was manipulated during the experiment by a centrally located arrow which could give neutral, valid (80%) or invalid cues (20%). Reaction time measures showed a cost for invalid trials relative to valid trials. This effective manipulation of attention for the valid and invalid trials had no effect on the RVF advantage relative to the baseline (neutral) trials. It was concluded that attentional biases play no significant role in the RVF advantage for two-flash fusion.
Publisher: Elsevier BV
Date: 03-2008
DOI: 10.1016/J.BANDC.2007.07.002
Abstract: This study investigated functional differences in the processing of visual temporal information between the left and right hemispheres (LH and RH). Participants indicated whether or not a checkerboard pattern contained a temporal gap lasting between 10 and 40 ms. When the stimulus contained a temporal signal (i.e. a gap), responses were more accurate for the right visual field-left hemisphere (RVF-LH) than for the left visual field-right hemisphere (LVF-RH). This RVF-LH advantage was larger for the shorter gap durations (Experiments 1 and 2), suggesting that the LH has finer temporal resolution than the RH, and is efficient for transient detection. In contrast, for noise trials (i.e. trial without temporal signals), there was a LVF-RH advantage. This LVF-RH advantage was observed when the entire stimulus duration was long (240 ms, Experiment 1), but was eliminated when the duration was short (120 ms, Experiment 2). In Experiment 3, where the gap was placed toward the end of the stimulus presentation, a LVF-RH advantage was found for noise trials whereas the RVF-LH advantage was eliminated for signal trials. It is likely that participants needed to monitor the stimulus for a longer period of time when the gap was absent (i.e. noise trials) or was placed toward the end of the presentation. The RH may therefore be more efficient in the sustained monitoring of visual temporal information whereas the LH is more efficient for transient detection.
Publisher: Wiley
Date: 18-07-2003
DOI: 10.1002/MDS.10528
Abstract: Previous research has demonstrated a relationship between the regularity of motor production and the ability to make accurate perceptual judgments. The current study investigated the temporal abilities of two groups of patients with known movement problems (musicians' and writers' cr ), some of whom have had many years of training in temporal discrimination. Patients and controls (musician and nonmusician, respectively) judged whether the last of six sequential auditory or tactile stimuli occurred earlier or later in comparison to five previously and regularly presented stimuli. In both sensory domains, patients with musicians' cr detected the early stimulus better than controls. When detecting the onset of late stimuli, only in the auditory domain were patients worse than controls. Patients with writers' cr , however, did not show any significant group differences in either auditory or tactile domains, suggesting that such patients are not deficient in processing sequential stimuli. In conclusion, compared to controls, patients with musician's cr demonstrated generalized timing anomalies, occurring in the symptomatic (tactile) and the asymptomatic (auditory) sensory domains. This timing problem is likely to be a consequence of the dystonic symptoms rather than the cause.
Publisher: Hogrefe Publishing Group
Date: 12-2010
DOI: 10.1027/1618-3169/A000037
Abstract: Numerical magnitude is coded left-to-right along a mental number line (MNL). The MNL can be distorted by an attentional bias directed to the left side, known as pseudoneglect – making the left of the MNL appear longer. We investigated whether this distortion can be corrected using spatial cues. Participants (n = 17) made forced-choice discriminations of relative numerical length while spatial cues were presented to the left, right, and both sides. Overall, participants overestimated the leftward length of the MNL, consistent with the effect of pseudoneglect. The bias was present for left- and neutral-cues, but was eliminated by right-cues. The results demonstrate that low-level manipulation of attention in physical space affects attention for high-level mental representations. The effect of cueing may reflect common activation of overlapping neural circuits that are thought to underlie attention in physical and representational space.
Publisher: Informa UK Limited
Date: 28-05-2015
DOI: 10.1080/17588928.2015.1048677
Abstract: While it is generally acknowledged that another person's presence can influence how we behave within our environment, our understanding of the mechanisms underlying this influence is limited. Three experiments investigated the effect of social presence on the lateral distribution of spatial attention. Shifts in spatial attention were measured using line bisection, while participants sat in each other's personal space. An attentional withdrawal was observed, whereby attention moved away from the other person when the same task was using turn-taking (Experiment 1) and independent responding (Experiment 2) paradigms. When participant pairs engaged in different tasks (Experiment 3), attentional withdrawal was no longer observed. Our results strongly suggest that the influence of interpersonal proximity on attention merits greater consideration than it has received from researchers investigating social effects on cognition.
Publisher: Wiley
Date: 19-03-2021
DOI: 10.1111/BJOP.12501
Abstract: The cheerleader effect occurs when the same face is rated to be more attractive when it is seen in a group compared to when seen alone. We investigated whether this phenomenon also occurs for trustworthiness judgements, and examined how these effects are influenced by the characteristics of the in idual being evaluated and those of the group they are seen in. Across three experiments, we reliably replicated the cheerleader effect. Most faces became more attractive in a group. Yet, the size of the cheerleader effect that each face experienced was not related to its own attractiveness, nor to the attractiveness of the group or the group’s digitally averaged face. We discuss the implications of our findings for the hierarchical encoding and contrast mechanisms that have previously been used to explain the cheerleader effect. Surprisingly, judgements of facial trustworthiness did not experience a ‘cheerleader effect’. Instead, we found that untrustworthy faces became significantly more trustworthy in all groups, while there was no change for faces that were already trustworthy alone. Taken together, our results demonstrate that social context can have a dissociable influence on our first impressions, depending on the trait being evaluated.
Publisher: Elsevier BV
Date: 05-2005
DOI: 10.1016/J.BANDL.2004.09.006
Abstract: The cerebral hemispheres have been proposed to engage different word recognition strategies: the left hemisphere implementing a parallel, and the right hemisphere, a sequential, analysis. To investigate this notion, we asked participants to name words with an early or late orthographic uniqueness point (OUP), presented horizontally to their left (LVF), right (RVF), or both fields of vision (BVF). Consistent with past foveal research, Experiment 1 produced a robust facilitatory effect of early OUP for RVF/BVF presentations, indicating the presence of sequential processes in lexical retrieval. The effect was absent for LVF trials, which we argue results from the disadvantaged position of initial letters of words presented in the LVF. To test this proposition, Experiment 2 assessed the discriminability of various letter positions in the visual fields using a bar-probe task. The obtained error functions highlighted the poor discriminability of initial letters in the LVF and latter letters in the RVF. To confirm that this asymmetry in initial letter acuity was responsible for the absent OUP effect for LVF presentations, Experiment 3 replicated Experiment 1 using vertical stimulus presentations. Results indicated a marked facilitatory effect of early OUP across visual fields, supporting our contention that the lack of OUP effect for LVF presentations in Experiment 1 resulted from poor discriminability of the initial letters. These findings confirm the presence of sequential processes in both left and right hemisphere word recognition, casting doubt on parallel models of word processing.
Publisher: Springer Science and Business Media LLC
Date: 05-05-2016
DOI: 10.3758/S13414-016-1122-7
Abstract: Clinical neglect patients overattend to stimuli on their right, whereas the general population overattend to the left (pseudoneglect). Both phenomena are affected by viewing distance, whereby the attentional biases are attenuated as the stimulus moves from near to far space. Both are also affected by stimulus length and reduce in strength, or even reverse (the crossover effect), as length decreases. To gain an insight into the cognitive/neural mechanisms that underlie the effects of viewing distance and stimulus length, in two experiments we examined the interaction between the variables. In Experiment 1 we asked university students (n = 20) to perform a horizontal landmark bisection task with lines presented at varying lengths (1.2°, 6.3°, and 18.4° of viewing angle) and distances (450 and 1,350 mm). A crossover effect and pseudoneglect were observed for the short and the long lines, respectively. An effect of viewing distance was only observed for long lines. Experiment 2 was the same, except that the lines were rotated to form vertical lines. No crossover effect was observed for the short lines, but an upward bias was observed for the long lines. Once again, an effect of viewing distance was only apparent for the long lines. These results demonstrate that the crossover effect is not a general property of short lines and is specific to the horizontal dimension. Models of crossover therefore need to incorporate processes related to left-right asymmetries. The results also demonstrate that viewing distance only affects long lines, and that this happens irrespective of orientation. A model of viewing distance is discussed that incorporates a right hemisphere mechanism specialized for an interaction between the ventral and dorsal streams.
Publisher: Wiley
Date: 12-2005
Abstract: Auditory evoked potentials (AEPs) were examined in patients with musician's cr (focal dystonia) in order to determine whether these patients have electrophysiological changes in a sensory system that is not usually associated with symptoms. All participants were professional guitarists and were required to listen to 2,000 monaurally presented stimuli (middle C, with duration of 7 ms). During one block, 250 stimuli were presented to one ear. Once a block was finished, another block was presented in the other ear in total there were eight blocks of stimuli. During this task, EEGs from 10 scalp electrodes and one bipolar eye channel were continuously recorded. There were no significant latency or topographical differences in the electrophysiological recordings. However, there was a significant group difference in the peak-to-peak litude of the P1-N1a component. The patients had a larger peak-to-peak difference than controls (1.63 vs. 0.62 microV). The P1 and N1a are cortically generated potentials. Patients with focal dystonia had an increase in activity compared to controls when processing simple auditory stimuli. Such changes in electrophysiological responses may be a result of increases in excitation or lack of inhibition alternatively the changes may represent cross-modal maladaptive plasticity from the somatosensory modality to the auditory modality. Thus, this study provides further evidence that patients with focal dystonia have alterations of the central nervous system that are not limited to their symptomatic sensory domain.
Publisher: American Psychological Association (APA)
Date: 2012
DOI: 10.1037/A0029151
Abstract: There is a persistent theory that birth stress and subsequent brain pathology play an important role in the manifestation of left-handedness. Evidence for this theory, however, is mixed and studies are often beset with problems related to small s le sizes and unreliable health reports. TO avoid these issues, this study used a s le of approximately 10,000 children from the British Cohort Study. The study contains objective birth-health reports and comprehensive measures of socioeconomic status, handedness, cognitive ability, and behavioral/health issues. Regression analyses showed that variables associated with birth stress affected cognitive/behavioral/health outcomes of the child. Despite this, these same factors did not affect the direction or degree of hand preference. We have therefore demonstrated a dissociation whereby adverse birth factors affect the brain's cognitive ability, but not handedness, and by implication, cerebral lateralization. The study also demonstrated a link between left-handedness and reduced levels of cognitive ability. This link cannot be due a generalized birth-stress mechanism and may be caused by specific mechanisms related to changes in cerebral dominance.
Publisher: Springer Science and Business Media LLC
Date: 29-07-2008
DOI: 10.1007/S00221-008-1502-X
Abstract: While patients with right parietal damage and spatial neglect bisect lines to the right, the general population bisects lines to the left a phenomenon known as pseudoneglect. The leftward bias also occurs for mental representations, such as number and alphabet lines. Prismatic adaptation can have a dramatic effect on attentional bias and corrects neglect and pseudoneglect for physical and mental number lines. This study examined whether prismatic adaptation can correct leftward bisection biases for alphabet lines, which may have a different spatial arrangement compared to number lines. In pre-adaptation testing, students (n = 42) were shown letter trigrams (e.g. C H P) and judged whether the alphabetical distance before or after the inner-letter was larger. Participants were then split into three groups and were adapted to left-shifting, control or right-shifting prims. After adaptation, the mental alphabet bisection task was re-administered. The length of left side of the alphabet lines was overestimated by all three groups in the pre-adaptation phase. Right-shifting prisms and control spectacles had no effect on the leftward bias whereas exposure to left-shifting prisms corrected the bias. The results replicate an effect observed for mental number lines and demonstrate that low-level sensory-motor shifts can correct attentional biases associated with high-level representations, such as letters.
Publisher: American Psychological Association (APA)
Date: 10-2016
DOI: 10.1037/XHP0000258
Abstract: In object perception studies, a response advantage arises when the handle of an object is congruent with the responding hand. This handle effect is thought to reflect increased motor activation of the hand most suited to grasp the object, consistent with affordance theories of object representation. An alternative explanation has been proposed, however, which suggests that the handle effect is related to a simple spatial compatibility effect (the Simon effect). In 3 experiments, we determined whether the handle effect would emerge in the absence of explicit spatial compatibility between handle and response. Stimulus and response location was varied vertically and participants made horizontally orthogonal, bimanual responses to objects' kitchen/garage category, color (as in a traditional Simon effect) or upright/inverted orientation. Categorization and inversion tasks, which relied on object knowledge, elicited a handle effect and a vertical Simon effect regarding stimulus and response locations. When participants judged object color, as per standard Simon effect paradigms, the handle effect disappeared but the Simon effect strengthened. These data demonstrate a dissociation between affordance and spatial compatibility effects and prove that affordance plays an important role in the handle effect. Models that incorporate both affordance and spatial compatibility mechanisms are discussed. (PsycINFO Database Record
Publisher: Elsevier BV
Date: 2006
DOI: 10.1016/S0010-9452(08)70360-5
Abstract: Leftward and upward perceptual biases are commonly reported for horizontal and vertical stimuli, respectively. It is unclear, however, whether these biases are based upon body or environment-centred coordinates. Two experiments examined the contribution of these coordinate systems to free-viewing vertical and horizontal perceptual biases. In Experiment 1, normal participants (n = 35) made forced-choice luminance judgments on two mirror-reversed luminance gradients (the 'greyscales' task) presented in vertical and horizontal orientations. Body and environment-based coordinates were dissociated by tilting participants' heads to the left or right. A leftward and upward bias, which was observed in the horizontal and vertical conditions (respectively) when the head was upright, was extinguished when the head was tilted. Results indicated a dual reliance on body and environmental coordinates with some suggestion that the upward bias was more dependent on environmental coordinates. In Experiment 2 the same stimuli were presented as participants (n = 24) adopted an upright or supine pose. Once again, leftward and upward biases were observed in the upright condition. The leftward bias persisted in the supine condition whereas the upward bias was eliminated. Results demonstrate that the leftward bias is based predominantly on body coordinates whereas the upward bias is reliant on environmental/gravitational coordinates. The possibility that the neural basis for the biases lies in the inter-modal centres of the intraparietal region of the right hemisphere is discussed.
Publisher: Informa UK Limited
Date: 26-02-2021
Publisher: Elsevier BV
Date: 2002
DOI: 10.1016/S0028-3932(02)00024-6
Abstract: Research, using composite facial photographs has demonstrated that left-left composites are more emotionally expressive than are right-right composites. The present study investigated whether hemifacial asymmetries in expression are apparent in photographs, that feature one side of the face more than the other. Photographs were taken of the models who turned their heads: (a) 15 degrees to the left, (b) 15 degrees to the right or (c) faced directly towards the camera. It was predicted that left hemiface and midline photographs would be judged as more emotionally expressive than right hemiface photographs, where the left hemiface is less prominent. Three hundred and eighty-four participants viewed photographs of the three posing conditions, and rated each photograph along an emotional expressivity scale. Midline and left hemiface portraits were rated as more emotionally expressive than were right hemiface portraits. To investigate whether this effect was caused by observer's aesthetic erceptual biases, mirror-reversed versions of the three posing conditions were included. Left hemiface and midline portraits were rated as more emotionally expressive, irrespective of whether they were mirror-reversed. It was concluded that head turns of just 15 degrees can bring about significant changes in the perceived emotionality. The relevance of these findings to painted portraits, which feature the left hemiface more than the right, is discussed.
Publisher: SAGE Publications
Date: 12-2012
DOI: 10.1080/17470218.2012.688979
Abstract: The original aim was to examine the effect of perceived distance, induced by the Ponzo illusion, on left/right asymmetries for line bisection. In Experiment 1, university students ( n = 29) made left/right bisection judgements for lines presented in the lower or upper half of the screen against backgrounds of the Ponzo stimuli, or a baseline. While the Ponzo illusion had relatively little effect on line bisection, elevation in the baseline condition had a strong effect, whereby the leftward bias was increased for upper lines. Experiment 2 ( n = 17) eliminated the effect of elevation by presenting the line in the middle and moving the Ponzo stimuli relative to the line. Despite this change, the leftward bias was still stronger in the upper condition in the baseline condition. The final experiment ( n = 17) investigated whether upper/lower visual stimulation, which was irrelevant to the task, affected asymmetries for line bisection. The results revealed that a rectangle presented in the upper half of the screen increased the leftward line bisection bias relative to a baseline and lower stimulation condition. These results corroborate neuroimaging research, showing increased right parietal activation associated with shifts of attention into the upper hemispace. This increased right parietal activation may increase the leftward attentional bias—resulting in a stronger leftward bias for line bisection.
Publisher: Elsevier BV
Date: 11-2003
DOI: 10.1016/S0278-2626(03)00125-8
Abstract: Divided visual-field research suggests that attentional factors may contribute to the left hemisphere's (LH) superiority for language processing. The LH's parallel recognition strategy, specialised for whole word encoding, is largely unaffected by the distribution of spatial attention. In contrast, the right hemisphere's (RH) serial, letter-by-letter strategy places far greater demands on attentional resources. By manipulating spatial attention, the present study gauged the effect of cueing the beginning vs. the end of the word on LH and RH naming latency. Results indicated no effect of cue position on LH performance, consistent with research indicating that the LH enjoys an attentional advantage, deploying attention in parallel across the stimulus. As anticipated, the RH showed a facilitatory effect of beginning cue, which draws spatial attention to the initial letter cluster, enabling efficient implementation of the RH's sequential strategy. These findings suggest that differences in attentional deployment contribute to hemispheric asymmetries for word recognition.
Publisher: Elsevier BV
Date: 04-2016
DOI: 10.1016/J.CORTEX.2016.01.013
Abstract: Neurologically normal in iduals demonstrate a reliable bias to the left side of space, known as pseudoneglect. The magnitude of this attentional asymmetry varies, depending on factors such as location within the visual field. Prior research has shown that the presence of distractors in the upper visual field increase leftward biases. The current study investigated whether brief distractors in the periphery, which recruit exogenous attention influence the strength of pseudoneglect. In addition, to further investigate the interaction of vertical and horizontal attentional asymmetries, a vertical landmark task with horizontally presented distractors was also performed. Experiment 1 findings illustrated that single visual field distractors led to stronger leftward biases, when compared to dual visual field distractors. Results also indicated that upward biases for vertical lines were unchanged by horizontal distractors. A baseline landmark task was included in Experiment 2 to allow for participants to be separated into left- and right-responder groups. Results showed that upper space distractors increased the magnitude of asymmetries scores depending on the baseline direction. Left-responders showed increased leftward biases and right-responders showed increased rightward biases when distractors were presented in upper space. As in Experiment 1, horizontal distractors did not influence upward biases. Furthermore, horizontal and vertical asymmetries were not correlated in either experiment. The current results demonstrate a novel influence of distractors on in idual differences in pseudoneglect, which is consistent with the suggestion that a subset of in iduals show reliable rightward biases. This highlights the importance of accounting for baseline attentional asymmetries.
Publisher: Informa UK Limited
Date: 27-02-2014
Publisher: SAGE Publications
Date: 2015
DOI: 10.1080/17470218.2014.925481
Abstract: Many studies use multiexperiment designs where experiments are carried out at different times of semester. When comparing between experiments, the data may be confounded by between-participants effects related to motivation. Research indicates that course-credit participants who engage in research early in semester have different personality and performance characteristics compared to those tested late in semester. This study examined whether the semester effect is caused by internal (inherent motivation of the participant) or external (looming exams, essays) factors. To do this, sustained attention and intrinsic/extrinsic motivation was measured in groups of course-credit ( n = 40) and paid ( n = 40) participants early and late in semester. While there was no difference in sustained attention between the groups early in semester, the course-credit group performed significantly worse late in semester. The course-credit group also showed a significant decrease in intrinsic motivation with time whereas the paid participants showed no change. Because changes were not seen for both groups, the semester difference cannot be due to external factors. Instead, the data demonstrate that course-credit participants who engage early have high sustained attention and intrinsic motivation compared to their late counterparts, who leave their participation to the last minute. Researchers who use multiexperimental designs across semester need to control for these effects—perhaps by using paid participants who do not vary across semester.
Publisher: SAGE Publications
Date: 02-2003
DOI: 10.1080/02724980244000341
Abstract: Words with an early or late orthographic uniqueness point and nonwords with an early or late orthographic deviation point were presented to the left, right, or both visual fields simultaneously. In Experiment 1, 20 participants made lexical decision judgements to horizontal stimulus presentations. In Experiment 2, a further 20 participants completed the task using vertical presentations to control for attentional biases. Consistent with previous research, words with earlier orthographic uniqueness points prompted faster responses across visual fields, regardless of stimulus orientation. Although research has suggested that the left hemisphere's superiority for language processing stems from a comparatively parallel processing strategy, with the right hemisphere reliant upon a serial mechanism, left and right visual field presentations were not differentially affected by orthographic uniqueness point. This suggests that differential sequential effects previously reported result during processes other than retrieval from the lexicon. The overall right visual field advantage observed using horizontal presentations disappeared when stimuli were presented vertically. Contrary to expectations, there was a facilitatory effect of late orthographic deviation point for horizontal nonword presentations. Overall, the results were interpreted as being consistent with predictions of a cohort model of word recognition, and they highlighted the effect of stimulus orientation on left and right hemisphere word recognition.
Publisher: Public Library of Science (PLoS)
Date: 24-08-2010
Publisher: Elsevier BV
Date: 2004
DOI: 10.1016/J.NEUROPSYCHOLOGIA.2003.07.007
Abstract: The two cerebral hemispheres in humans have been suggested to control contralaterally opposed attentional biases. These biases may be revealed by unilateral hemispheric damage, which often causes contralesional spatial neglect, particularly when the right hemisphere (RH) is affected. Subtle attentional biases have also been observed in normal observers in tasks requiring judgements of horizontal spatial extent, brightness, numerosity and size. Here, we examined attentional biases for judging the darker of two left-right mirror-reversed brightness gradients under conditions of free viewing (the greyscales task). We compared performances of patients with damage to the RH (n=78) and left hemisphere (LH n=20) with those of normal controls (n=20). Controls showed a small but significant leftward bias, implying a subtle asymmetry favouring the RH. In contrast, RH and LH patients showed extreme rightward and leftward biases, respectively, both of which differed significantly from that of controls. For the patient groups, performance on clinical tests of neglect (cancellation and line bisection) did not predict their greyscales scores. Pathological biases were present in patients without clinical neglect or visual field defects, suggesting that the attentional bias measured by the greyscales task can be dissociated from clinical neglect and visual sensory loss. The greyscales task offers an efficient means of quantifying pathological attentional biases in unilateral lesion patients it is easy to administer and score, and may be particularly useful for clinical trials of recovery and rehabilitation following stroke.
Publisher: Elsevier BV
Date: 09-2012
DOI: 10.1016/J.NEUROPSYCHOLOGIA.2012.07.003
Abstract: The general population shows an attentional bias to the left, known as pseudoneglect. This bias is thought to be driven by higher levels of activation in right parietal areas. Using transcranial direct current stimulation (tDCS) to manipulate activation, this study examined whether tDCS over the left and right posterior parietal cortices (PPC) affects pseudoneglect. Normal participants received tDCS over the left or right PPCs (15 in each group). Pseudoneglect was measured using the greyscales task, which requires a forced-choice discrimination of luminance between two opposing luminance gradients. The greyscales task was administered both before and after (a) anodal (b) cathodal and (c) sham tDCS. Participants who received tDCS over the left PPC demonstrated pseudoneglect for the greyscales task, which was significantly reduced by anodal tDCS, but was unaffected by sham or cathodal tDCS. In contrast, for those participants who received right PPC tDCS, pseudoneglect for the greyscales task was unaffected by tDCS. Anodal tDCS, which is known to elevate neural excitation, may have overcome lower levels of activation in the left PPC, resulting in decreased pseudoneglect. These findings provide convincing evidence in support of an activation-orientation model of pseudoneglect and have implications for models of left neglect.
Publisher: SAGE Publications
Date: 23-01-2013
Abstract: The aim of this study was to investigate asymmetrical interactions between humans and their environment using online seat booking sites. Functional differences between the cerebral hemispheres affect the choices people make. For ex le, when asked to imagine going to a cinema, people preferentially select seats to the right. We investigated whether this experimental research generalizes to online booking sites for aircraft and theaters. Occupancy rates for seats taken on the left and right sides were assessed for 100 airline flights with 12,762 available seats and 37 theater performances with 34,456 seats. On the basis of previous research, a rightward bias was predicted for aircraft and theaters. For aircraft, contrary to expectation, occupancy rate was higher for left-compared with right-side seats. For theaters, a rightward bias was observed when the theater was less than half full. The bias was not affected by the orientation of the map. For aircraft, the leftward preference could be attributable to a rightward turning bias or a “feeling” that the port seats are closer to the exit, even though they are not. For theaters, the data demonstrate that the rightward preference observed in earlier studies exists only when the theater is relatively empty. Asymmetrical seating may play an important role in the efficient assimilation of information from the environment, and this role should take this into account when designing effective human–environment interfaces. The online method of assessing seating used in the current study provides an informative and potentially powerful means of assessing asymmetries in human perception and action.
Publisher: Elsevier BV
Date: 05-2011
DOI: 10.1016/J.PSYCHRES.2010.11.019
Abstract: Research on the sub-clinical condition of schizotypy suggests that it is associated with mixed handedness. To date, however, this research has focussed on undergraduate populations. If the association between schizotypy and mixed-handedness is the result of an underlying neurological trait, it is important to demonstrate that the effect extends to the general population. With this in mind, 699 participants were drawn from a wide community s le. Schizotypy was measured using the Psychosis Proneness Questionnaire and handedness was assessed using the Annett inventory. To avoid the sometimes arbitrary definitions of left-, right- and mixed-handed, regression analyses were used to explore the data. There was no evidence of a difference in schizotypy between in iduals with a left- or right-hand preference. People with a mixed-hand preference, however, had higher scores on PER-MAG (Perceptual Aberration and Magical Ideation) and HYP-IMP (Hypomania and Impulsive Non-Conformity) scales (positive traits). No effect was observed for the SAN (Social Anhedonia) and PAN (Physical Anhedonia) scales (negative traits). The nature of the association between schizotypy and handedness observed in the current study is similar to that reported for student populations. The possibility that the association is related to response biases or a biological mechanism is discussed.
Publisher: The Japanese Psychological Association
Date: 2014
Abstract: Quantitative assessment of handedness is required in various clinical and research settings in psychology, neuroscience, and medicine. In the present study we tested the reliability and validity of a Japanese version of the FLANDERS handedness questionnaire, which was a new measure of skilled hand preference originally reported by Nicholls, Thomas, Loetscher, and Grimshaw (2013). Participants (N=431) completed three types of handedness questionnaires: the FLANDERS handedness questionnaire, Edinburgh Handedness Inventory, and H · N handedness test. Factor analysis revealed that the Japanese version of FLANDERS handedness questionnaire had a single-factor structure and high internal consistency. This questionnaire also posssed high test-retest reliability and criterion-referenced validity. These results indicate that the Japanese version of the FLANDERS handedness questionnaire is a valid and useful measure of skilled hand preference for Japanese participants.
Publisher: Cambridge University Press (CUP)
Date: 27-04-2010
DOI: 10.1017/S1355617710000184
Abstract: The idea that handedness indicates something about a person’s cognitive ability and personality is a perennial issue. A variety of models have been put forward to explain this relationship and predict a range of outcomes from higher levels of cognitive ability in left-handers or moderate right-handers to lower levels of achievement in left- or mixed-handers. We tested these models using a s le ( n = 895) drawn from the BRAINnet database ( www.brainnet.net ). Participants completed a general cognitive ability (GCA) scale and a test of hand preference erformance. Moderate right-handers, as indexed by their performance measures, had higher GCA scores compared with strong left- or right-handers. The performance measure also showed lower levels of GCA for left-handers compared with right-handers. The hand preference data showed little or no association with cognitive ability—perhaps because this measure clusters in iduals toward the extremes of the handedness distribution. While adding support to Annett’s heterozygous advantage model, which predicts a cognitive disadvantage for strong left- or right-handers, the data also confirm recent research showing a GCA disadvantage for left-handers. Although this study demonstrates that handedness is related to cognitive ability, the effects are subtle and might only be identified in large-scale studies with sensitive measures of hand performance. ( JINS , 2010, 16 , 585–592.)
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 28-05-2008
Publisher: Elsevier BV
Date: 11-2013
DOI: 10.1016/J.CORTEX.2013.02.002
Abstract: Knowing whether an in idual prefers the left or right hand for skilled activities is important to researchers in experimental psychology and neuroscience. The current study reports on a new measure of skilled hand preference derived from the Provins and Cunliffe (1972) handedness inventory. Undergraduates (n = 3324) indicated their lateral preference for their hands, feet, eyes and ears. A measure of hand performance and familial handedness was also obtained. Factor analysis identified ten items that loaded on skilled hand preference and these were included in the new FLANDERS questionnaire. Cluster analysis of the new questionnaire revealed three distinct groups (left-, mixed- & right-handed). The new test showed a strong association with other measures of lateral preference and hand performance. Scores on the test were also related to the sex of the respondent and the hand preference of their parents. The FLANDERS provides a measure of skilled hand preference that is easy to administer and understand and should be useful for experimenters wanting to screen for hand preference.
Publisher: Elsevier
Date: 2016
Publisher: SAGE Publications
Date: 12-2006
Publisher: Elsevier BV
Date: 02-2017
DOI: 10.1016/J.NEUROPSYCHOLOGIA.2017.01.002
Abstract: Attention is asymmetrically distributed across the visual field, such that left side stimuli are more salient, which causes a spatial bias known as pseudoneglect. Although auditory cues can be used to direct visual attention to a location, the influence of auditory distractors on visuospatial asymmetries remains unknown. We examined whether attentional orienting or arousal effects occur when either left or right auditory distractors are presented during the landmark task. We also categorised participants based on the baseline direction of pseudoneglect. Experiment 1 showed a strong attentional orienting effect. A slightly weaker arousal effect was also observed. Interestingly, these effects appear to be additive, such that infrequent right ear distractors rendered leftward biases non-significant. A second experiment, using centralised auditory distractors, was conducted to isolate the role of arousal. A strong arousal effect occurred, which was mediated by baseline direction of pseudoneglect. Left- and right-responders showed parallel decreases in the strength of attentional asymmetries, as biases decreased in the presence of distractors. Importantly, these decreases were not accompanied by an increase in accuracy. We conclude that both attentional orienting and arousal mechanisms contribute to the cross-modal integration of auditory and visual information during visuospatial processing, with the role of attentional orienting being more dominant.
Publisher: American Psychological Association (APA)
Date: 2014
DOI: 10.1037/A0037033
Abstract: Quick and accurate judgments of emotional expressivity and attractiveness facilitate social interactions. Eye tracking was used to examine left/right asymmetries across 2 studies. Fixations to each hemiface, and to the eyes and mouth, when judging attractiveness and emotional expressivity were examined. Overall, more fixations occurred on the left hemiface (from the viewer's point of view), even when mirror-reversed, supporting the suggestion that we intuitively know the left hemiface is more expressive. The right side of the mouth was fixated more when judging happiness, whereas the left eye was fixated more for sadness and the left mouth when rating emotional expressivity. The present findings support the notion that the right hemisphere and valence-specific hypotheses are not mutually exclusive. The right hemisphere hypothesis is supported when assessing global facial qualities (i.e., hemiface) however, hemispheric processing differences emerge when exploring the eyes and mouth. The current findings highlight the importance of not only considering how the face is examined more generally, but of also exploring smaller regions of interest to investigate lateral biases. Future research should therefore include analyses of fixations to the hemifaces, as well as to these smaller regions of interest.
Publisher: SAGE Publications
Date: 2010
DOI: 10.1068/P6519
Abstract: The bodily boundaries in utees may seem to be more malleable than in non- utees, given the propensity for a phantom limb to embody a mirror-reflected hand. However, in the present investigation, in which phantom-limb illusions within body space are induced and manipulated, we found that perceiving phantom sensations and illusory embodiment does not require utation. Surprisingly, in the present modified rubber-hand illusion, we found that simultaneous stroking or stimulation of the participant's target hand was not necessary to induce illusions of embodiment and corresponding perceptual illusions. We tested this upper-limb paradigm in fourteen upper-limb utees and twenty-six controls (including fourteen lower-limb utees). We propose a model for embodiment of a rubber or real hand passively observed in a mirror. In this model, passive observation of the hand in the mirror triggers body representations (body image and body schema), most likely through activation of the posterior parietal cortex and temporo-parietal junction. Activity in these regions heightens awareness of peripersonal space and increases tactile sensitivity, and may subsequently enhance perception of illusory touch and embodiment. Furthermore, sense of embodiment may be more apparent to the participant when the hand is threatened however, embodiment may even be strengthened when the motor system is engaged, evoking motor schemata to support the more easily induced perceptual embodiment via body image.
Publisher: Springer Science and Business Media LLC
Date: 24-05-2012
DOI: 10.1007/S00221-012-3113-9
Abstract: Neurologically normal in iduals show an attentional bias toward the left side, which results from right hemisphere activation during visuospatial tasks. The strength of this bias is influenced by various factors, such as line length, vertical elevation and presentation time. What remains unknown is how participants gather information via saccadic eye movements during task performance and how this relates to their responses. Eye movements were recorded while participants performed the landmark task. Fixations and saccades were both analysed to gain a complete understanding of eye movement patterns. Fixations tended to focus on the centre of the line, with few left-right differences. Saccades were examined by creating histograms illustrating all x-coordinates which were examined over the course of each trial. Interestingly, mean eye position varied with participant response, with an overall tendency to look to the right of centre. Results are consistent with prior research, which has primarily looked at fixations and demonstrates the necessity of examining saccades as well as fixations in order to see how eye movement patterns relate to pseudoneglect.
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 20-07-2012
DOI: 10.1167/12.7.9
Abstract: We investigated the claim that larger stimuli are perceived to last longer (Xuan, Zhang, He, & Chen, 2007). This claim, along with other similar claims of interactions between magnitude representations, is frequently used to support the generalized magnitude system hypothesis-the suggestion that the brain represents information about different magnitudes (e.g., time, space, and quantity) via a common mechanism. It is not clear, however, whether the size of a stimulus genuinely affects the perceived duration of the stimulus or simply biases decisions about duration. This was addressed using duration "equality judgments," which have been proposed to measure perceived duration unconfounded by decisional bias-in contrast to "comparative judgments," which are generally considered bias-prone. Using equality judgments, we failed to find support for the claim that larger stimuli are perceived to last longer, despite replicating the original effect reported by Xuan et al. (2007) using comparative judgments. Instead, unexpectedly, larger stimuli were judged-though not necessarily perceived-as shorter in duration. This result casts doubt on the conclusions of a significant body of behavioral interference studies using comparative judgments, which support a generalized magnitude system. We also identify a hitherto unrecognized potential source of decisional bias associated with equality judgments.
Publisher: Frontiers Media SA
Date: 2013
Publisher: Elsevier BV
Date: 06-2006
DOI: 10.1016/J.BANDL.2005.11.007
Abstract: This study explored asymmetries for movement, expression and perception of visual speech. Sixteen dextral models were videoed as they articulated: 'bat,' 'cat,' 'fat,' and 'sat.' Measurements revealed that the right side of the mouth was opened wider and for a longer period than the left. The asymmetry was accentuated at the beginning and ends of the vocalization and was attenuated for words where the lips did not articulate the first consonant. To measure asymmetries in expressivity, 20 dextral observers watched silent videos and reported what was said. The model's mouth was covered so that the left, right or both sides were visible. Fewer errors were made when the right mouth was visible compared to the left--suggesting that the right side is more visually expressive of speech. Investigation of asymmetries in perception using mirror-reversed clips revealed that participants did not preferentially attend to one side of the speaker's face. A correlational analysis revealed an association between movement and expressivity whereby a more motile right mouth led to stronger visual expressivity of the right mouth. The asymmetries are most likely driven by left hemisphere specialization for language, which causes a rightward motoric bias.
Publisher: Springer Science and Business Media LLC
Date: 25-05-2011
Abstract: We describe the case of a patient who experienced phantom pain that began 42 years after right above-the-knee utation. Immediately prior to phantom pain onset, this long-term utee had experienced, in rapid succession, cancer, hemicolectomy, chemotherapy, and thrombotic occlusion. Very little has been published to date on the association between chemotherapy and exacerbation of neuropathic pain in utees, let alone the phenomenon of bringing about pain in utees who have been pain-free for many decades. While this patient presented with a unique profile following a rare sequence of medical events, his case should be recognized considering the frequent co-occurrence of osteomyelitis, chemotherapy, and utation. A 68-year-old Australian Caucasian man presented 42 years after right above-the-knee utation with phantom pain immediately following hemicolectomy, thrombotic occlusion in the utated leg, and chemotherapy treatment with leucovorin and 5-fluorouracil. He exhibited probable hyperalgesia with a reduced pinprick threshold and increased stump sensitivity, indicating likely peripheral and central sensitization. Our patient, who had long-term nerve injury due to utation, together with recent ischemic nerve and tissue injury due to thrombosis, exhibited likely chemotherapy-induced neuropathy. While he presented with unique treatment needs, cases such as this one may actually be quite common considering that osteosarcoma can frequently lead to utation and be followed by chemotherapy. The increased susceptibility of utees to developing potentially intractable chemotherapy-induced neuropathic pain should be taken into consideration throughout the course of chemotherapy treatment. Patients in whom chronic phantom pain then develops, perhaps together with mobility issues, inevitably place greater demands on healthcare service providers that require treatment by various clinical specialists, including oncologists, neurologists, prosthetists, and, most frequently, general practitioners.
Publisher: SAGE Publications
Date: 03-2017
DOI: 10.1080/17470218.2015.1131841
Abstract: Perceptual attention in healthy participants is characterized by two biases, one operating in the horizontal plane, which draws attention leftward, and the other operating in the vertical plane, which draws attention upward. Given that these biases are reliably found in the same in idual, and appear similar at a surface level, a number of researchers have investigated the relationship between horizontal and vertical attentional biases. To date, these investigations have failed to find an association, and this may be due to the fact that one-dimensional vertical and horizontal stimuli were presented separately rather than being measured from a single, two-dimensional stimulus. Across three experiments, two dimensional stimuli were presented, and participants marked the centre of the stimuli. In addition, the shapes of the stimuli were manipulated to determine whether this produced the same modulation of the two biases. Across 13 stimuli and three experiments there were no correlations between the vertical and horizontal biases. In addition, manipulations of stimulus shape, which affected biases in one dimension, did not affect biases in the other dimension. There were, however, consistent correlations between the degree of bias within each dimension across the different stimuli. This study has produced converging evidence that horizontal and vertical biases in spatial judgments rely on separate cognitive mechanisms. To account for these results we discuss a model whereby horizontal asymmetries rely more on space-based mechanisms whereas vertical asymmetries rely more on object-based mechanisms.
Publisher: The Royal Society
Date: 07-04-2004
Publisher: Springer Science and Business Media LLC
Date: 26-03-2018
DOI: 10.1038/S41598-018-23498-W
Abstract: Research using the irrelevant-distractor paradigm shows perceptual load influences distractibility, such that distractors are more likely to be processed and decrease reaction times during low perceptual load. In contrast, under high load, attentional resources are limited, and the likelihood of distractibility is decreased. We manipulated distractor placement to determine whether location differentially influenced distractibility. During low load, reaction times were increased equally for all distractor locations. Under high load, left distractors speeded reaction times significantly more than right distractors. We suggest two potential explanations: (1) the central focus of attention was sufficiently large to encapsulate both the distractor and the visual array during low perceptual load, leading to increased distraction—during high load, attention was split across the two visual stimuli, allowing the distractors and array to be processed independently (2) superior executive control for stimuli in the left visual field allowed participants to ‘catch and release’ left distractors more efficiently, ultimately decreasing distraction and providing a performance benefit. Our findings represent an intriguing development in relation to visual asymmetries in distractibility.
Publisher: Informa UK Limited
Date: 06-01-2014
DOI: 10.1080/17470919.2013.873737
Abstract: It is now common practice, in digital communication, to use the character combination ":-)", known as an emoticon, to indicate a smiling face. Although emoticons are readily interpreted as smiling faces, it is unclear whether emoticons trigger face-specific mechanisms or whether separate systems are utilized. A hallmark of face perception is the utilization of regions in the occipitotemporal cortex, which are sensitive to configural processing. We recorded the N170 event-related potential to investigate the way in which emoticons are perceived. Inverting faces produces a larger and later N170 while inverting objects which are perceived featurally rather than configurally reduces the litude of the N170. We presented 20 participants with images of upright and inverted faces, emoticons and meaningless strings of characters. Emoticons showed a large litude N170 when upright and a decrease in litude when inverted, the opposite pattern to that shown by faces. This indicates that when upright, emoticons are processed in occipitotemporal sites similarly to faces due to their familiar configuration. However, the characters which indicate the physiognomic features of emoticons are not recognized by the more laterally placed facial feature detection systems used in processing inverted faces.
Publisher: Elsevier BV
Date: 11-1997
DOI: 10.1016/S0028-3932(97)00063-8
Abstract: A dichotomy is thought to exist between the hemispheres whereby the right hemisphere is specialized for the processing of negative emotions and the left hemisphere is specialized for positive emotions. Van Strien and Morpurgo (Neuropsychologia, 1992, 30, 845-848) demonstrated that the activation of negative and positive emotional states resulted in the allocation of attentional resources to the contralateral hemispace. In the present experiment we sought to replicate this effect and improve upon certain methodological features of the experiment. The effect of positive and negative emotions on performance in the left and right visual fields was investigated in 30 dextral students. Positive and negative emotional states were generated by presenting subjects with an emotive word prior to each trial and subsequently requiring them to use that word within a sentence. Performance within the left and right fields was measured using a gap detection task which was neutral in relation to functional asymmetry. No evidence of right or left visual field facilitation was found for the positive or negative conditions, respectively. These results are not interpreted as a refutation of hemispheric specialization for emotional valence. Instead, they are seen to highlight the frailty of hemispheric facilitation effects.
Publisher: Springer Science and Business Media LLC
Date: 10-12-2004
DOI: 10.1007/S00221-004-2196-3
Abstract: Two experiments investigated the contribution of space- and object-based coordinates to previously reported leftward perceptual biases (pseudoneglect) at various locations across visual space. Neurologically intact participants (n = 34 and 27) made luminance discriminations between two left/right mirror-reversed luminance gradients (greyscales task), which were variously displaced around the midline in the participants' left and right hemispaces. The orientations of the stimuli were manipulated so that object- and space-based coordinates were congruent or incongruent. Experiment 1 confirmed the presence of a leftward object-based perceptual bias. The bias was moderated, however, by overattention to the more central stimulus. This central spatial effect could have resulted from the use of task-specific strategies, which were controlled by presenting the stimuli sequentially in Experiment 2. The findings of Experiment 1, a leftward object-based bias and a central spatial bias, were replicated. Overall, the results indicate a leftward object-based bias and a central spatial bias, both of which are relevant for the allocation of attention. The results are discussed with reference to a variety of models of the distribution of attention across space.
Publisher: Elsevier BV
Date: 11-2003
DOI: 10.1016/S0278-2626(03)00120-9
Abstract: Turning the trunk or head to the left can reduce the severity of leftward neglect. This study sought to determine whether turning the trunk or head to the right would reduce pseudoneglect: A phenomenon where normal participants underestimate the rightward features of a stimulus. Participants made luminance judgements of two mirror-reversed greyscales stimuli. A preference for selecting the stimulus dark on the left was found. The effect of trunk-centred coordinates was examined in Expt. 1 by facing the head toward the display and turning the trunk to the left, right or toward the display. Head-centred coordinates were examined in Expt. 2 by directing the eyes toward the display and then turning the head and trunk. No effect of rotation was observed. It was concluded that the leftward bias for the greyscales task could be based on an object-centred attentional bias or left-to-right eye scanning habits.
Publisher: Public Library of Science (PLoS)
Date: 11-08-2011
Publisher: SAGE Publications
Date: 2010
DOI: 10.1068/P6582
Abstract: Pain synaesthetes experience pain in a presensitised region when observing or imagining another person in pain. We conducted an upper-limb embodiment study using a modified rubber-hand illusion in which lower-limb utees originally participated as control subjects for the upper-limb utees. While we found all subjects experienced topographic illusory sensations, we also serendipitously found that lower-limb utee pain synaesthetes experienced pain or a motor response in their phantom leg when the embodied hand was threatened (eg with a retractable knife, mousetrap, or syringe) or submitted to high-frequency stimulation (eg vibration). Embodiment illusions were brought about by touching, manipulating, or threatening a rubber or real hand which was observed through a mirror so that it was superimposed upon the target hand (phantom hand for upper-limb utees, or real hand in others). Participants included eight pain synaesthetes (six lower-limb utees, one upper-limb utee, and one non utee), and thirty-one controls (eight lower-limb utees, twelve upper-limb utees, and eleven non- utees). We documented participant's subjective reports, together with quantitative measures including the Questionnaire Measure of Emotional Empathy. We found no association between pain synaesthesia and empathy scores. On the basis of related literature we suggest that pain synaesthetes likely experienced phantom-leg pain because (a) the motor system was already engaged during visual capture (b) threatening stimuli, to which they are hyper-vigilant, triggered avoidance or ‘escape’ motor schemata and (c) there could be no feedback confirming that initiated motor schemata for the phantom limb were successfully performed. Ultimately, we have further defined this new condition, synaesthesia for pain, as not only having a sensory pain component, but also a key motor component, manifesting itself in avoidance, contraction, and withdrawal ‘actions’.
Publisher: Springer Science and Business Media LLC
Date: 07-02-2018
DOI: 10.1038/S41598-018-20784-5
Abstract: The cheerleader effect occurs when the same in idual appears to be more attractive when seen in a group, compared to alone. As observers over-attend to visual information presented in the left visual field, we investigated whether the spatial arrangement of the faces in a group would influence the magnitude of the cheerleader effect. In Experiment 1, target faces were presented twice in the centre of the display: once alone, and once in a group. Group images featured two distractor faces , which were presented in either the left or the right visual field, or on either side of the target. The location of the distractor faces did not modulate the size of the cheerleader effect, which was observed in each group configuration. In Experiment 2, we manipulated the location of the target faces , which were presented at the far left, far right, or centre of the group. Faces were again significantly more attractive in each group configuration, and the spatial location of the target face did not influence the size of the cheerleader effect. Together, our results show that the cheerleader effect is a robust phenomenon, which is not influenced by the spatial arrangement of the faces in the group.
Publisher: Hogrefe Publishing Group
Date: 2003
DOI: 10.1027/0269-8803.17.4.195
Abstract: AbstractSimple tapping and complex movements (Luria finger apposition task) were performed unimanually and bimanually by two groups of professional guitarists while EEG was recorded from electrodes over the sensorimotor cortex. One group had a task-specific movement disorder (focal dystonia or musicians' cr ), while the other group did not (controls). There were no significant group interactions in the task-related power (TRPow) within the alpha range of 8-10Hz (mu1). In contrast, there was a significant group interaction within the alpha range of 10-12Hz (mu2) these latter frequencies are associated with task-specific sensorimotor integration. The significant group interaction included task (simple and complex) by hand (left, right, and both) by electrodes (10 electrodes over the sensorimotor areas). In the rest conditions, the alpha power (10-12Hz) was comparable between the groups during movement, however, compared to the controls, patients demonstrated the greatest TRPow (10-12Hz) over all conditions. This was particularly evident when patients used their affected hand and suggests that patients with musicians' cr have impaired task-specific sensorimotor integration.
Publisher: Elsevier BV
Date: 03-2015
DOI: 10.1016/J.CORTEX.2014.10.018
Abstract: Pseudoneglect is influenced by vertical visual field stimulation, such that attentional biases are stronger for upper space distractors. Leftward biases result from right hemisphere visuospatial processing, and may be accentuated by additional right hemisphere activation during upper space distraction. Three experiments examined potential explanations for this finding. Experiment 1 controlled for perceptual grouping and leftward biases remained stronger in upper space. Experiment 2 used peripheral distractors to eliminate two further potential explanations: centre-of-mass and framing effects. Eye tracking was included to compare overt and covert attention. Findings supported the occurrence of a stronger leftward attentional bias during upper space distraction. Distractors were rarely fixated, suggesting covert attentional mechanisms are preferentially drawn toward upper space distractors. Experiment 3 employed a cueing paradigm that purposefully directed attention away from centre to determine whether pseudoneglect was influenced by overt attentional orienting. Results indicated that when attention was overtly directed away from centre, the strength of pseudoneglect did not differ based on visual field. It is concluded that covert attention toward upper space distractors recruits additional right hemisphere activation, leading existing leftward biases to be accentuated.
Publisher: Elsevier BV
Date: 04-2011
DOI: 10.1016/J.BANDC.2010.12.005
Abstract: Perceptual asymmetries for tasks involving aesthetic preference or line bisection can be affected by asymmetrical neurological mechanisms or left/right reading habits. This study investigated the relative contribution of these mechanisms in 100 readers of Japanese and English. Participants made aesthetic judgments between pairs of mirror-reversed pictures showing: (a) static objects, (b) moving objects and (c) landscapes. A line bisection task was also administered. There was a strong effect of reading direction for static and mobile objects whereby Japanese readers preferred objects with a right-to-left directionality (and vice versa for English readers). In contrast, similar patterns were observed for the Japanese and English readers for the landscape and line bisection tasks. The results show that reading habits affect aesthetic judgments for static and moving object tasks, but not the landscape and line bisection tasks. The difference between the tasks may be related to the horizontal/vertical geometry of the stimuli, which makes the landscape and line bisection tasks more prone to universal effects related to cerebral dominance.
Publisher: Springer Science and Business Media LLC
Date: 08-12-2015
DOI: 10.1007/S00221-015-4504-5
Abstract: Research suggests that the left cerebral hemisphere is predisposed for processing stimuli in 'near' space, whereas the right hemisphere is specialised for processing stimuli in 'far' space. This hypothesis was tested directly by asking 25 undergraduates to carry out a landmark radial line bisection task. To test the effect of hemispheric differences in processing, the lines were placed to the left, right or centre within the transverse plane. Consistent with predictions, lines in all three conditions were bisected distal to the true centre. More importantly, there was an asymmetry whereby the distal bias was stronger for lines presented in the left hemispace compared to the right hemispace. The results demonstrate that the perception of depth is affected by left/right placement along the lateral axis and highlight the cognitive/neural interplay between the radial and lateral axes.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 10-2011
Publisher: American Psychological Association (APA)
Date: 29-10-2020
DOI: 10.1037/XHP0000863
Publisher: Elsevier BV
Date: 12-2005
DOI: 10.1016/J.BANDC.2005.07.007
Abstract: This study investigates whether the right hemisphere has more flexible contrast gain control settings for the identification of spatial frequency. Right-handed participants identified 1 and 9 cycles per degree sinusoidal gratings presented either to the left visual field-right hemisphere (LVF-RH) or the right visual field-left hemisphere (RVF-LH). When luminance contrast was randomized across a wide range (20-60%), performance gradually improved with contrast in the LVF-RH. Conversely, performance in the RVF-LH was disrupted and saturated for 20 and 60% of contrast, respectively, leading to a LVF-RH advantage for these contrast levels. When contrast was blocked or randomized for a smaller range (30-50%), the LVF-RH advantage was diminished. Flexible contrast gain control is needed when contrast is randomized across a wide range, but not when it is blocked or randomized across a smaller range. The results therefore suggest that the right hemisphere is able to process spatial frequency information across a wider range of contrast levels than is the left hemisphere.
Publisher: Springer Science and Business Media LLC
Date: 09-2018
DOI: 10.3758/S13414-017-1413-7
Abstract: Research suggests that the human brain codes manipulable objects as possibilities for action, or affordances, particularly objects close to the body. Near-body space is not only a zone for body-environment interaction but also is socially relevant, as we are driven to preserve our near-body, personal space from others. The current, novel study investigated how close proximity of a stranger modulates visuomotor processing of object affordances in shared, social space. Participants performed a behavioural object recognition task both alone and with a human confederate. All object images were in participants' reachable space but appeared relatively closer to the participant or the confederate. Results revealed when participants were alone, objects in both locations produced an affordance congruency effect but when the confederate was present, only objects nearer the participant elicited the effect. Findings suggest space is ided between strangers to preserve independent near-body space boundaries, and in turn this process influences motor coding for stimuli within that social space. To demonstrate that this visuomotor modulation represents a social phenomenon, rather than a general, attentional effect, two subsequent experiments employed nonhuman joint conditions. Neither a small, Japanese, waving cat statue (Experiment 2) nor a metronome (Experiment 3) modulated the affordance effect as in Experiment 1. These findings suggest a truly social explanation of the key interaction from Experiment 1. This study represents an important step toward understanding object affordance processing in real-world, social contexts and has implications broadly across fields of social action and cognition, and body space representation.
Publisher: Public Library of Science (PLoS)
Date: 11-10-2017
Publisher: The Royal Society
Date: 07-08-1999
Publisher: SAGE Publications
Date: 05-1994
DOI: 10.1080/14640749408401113
Abstract: Divided visual field techniques were used to investigate hemispheric asymmetries for (a) the threshold of fusion of two flashes of light and (b) the detection of simultaneous versus successive events for a group of normal, right-handed adults. A signal detection analysis revealed a higher level of accuracy for the right visual field-left hemisphere (RVF-LH) relative to the left visual field-right hemisphere (LVF-RH) for both tasks. These results were interpreted in terms of a general left-hemisphere advantage for the discrimination of fine temporal events. The implications of these results for models of temporary asymmetry that describe the left hemisphere's advantage in terms of an exclusive specialization or relative superiority are then discussed.
Publisher: Elsevier BV
Date: 09-1996
DOI: 10.1016/0028-3932(96)00004-8
Abstract: The proposition that visual field asymmetries can be produced through priming the left hemisphere with verbal material was investigated. In the first experiment a two-choice neutral detection task was established to measure biases of attention between the visual fields. In the second experiment, a priming effect was achieved by superimposing each trial with a verbal recognition task. Reaction time and error measures showed no sign of a right visual field advantage. In the third experiment, the neutral detection trials were intermixed with trials associated with a word recognition task. A significant right visual field advantage was found for the word recognition task. However, this pattern of asymmetry was not found for the neutral detection task. In the fourth experiment the level of difficulty associated with neutral detection task was increased. The effect of expectancy was investigated by manipulating the proportion of neutral and verbal stimuli. Despite these manipulations, the pattern of results was essentially the same as those observed in the previous experiment. These experiments demonstrate that verbal priming does not affect the distribution of spatial attention.
Publisher: Elsevier BV
Date: 04-2002
DOI: 10.1016/S0167-8760(01)00190-8
Abstract: Lateralization for temporal processing was investigated using evoked potentials to an auditory and visual gap detection task in 12 dextral adults. The auditory stimuli consisted of 300-ms bursts of white noise, half of which contained an interruption lasting 4 or 6 ms. The visual stimuli consisted of 130-ms flashes of light, half of which contained a gap lasting 6 or 8 ms. The stimuli were presented bilaterally to both ears or both visual fields. Participants made a forced two-choice discrimination using a bimanual response. Manipulations of the task had no effect on the early evoked components. However, an effect was observed for a late positive component, which occurred approximately 300-400 ms following gap presentation. This component tended to be later and lower in litude for the more difficult stimulus conditions. An index of the capacity to discriminate gap from no-gap stimuli was gained by calculating the difference waveform between these conditions. The peak of the difference waveform was delayed for the short-gap stimuli relative to the long-gap stimuli, reflecting decreased levels of difficulty associated with the latter stimuli. Topographic maps of the difference waveforms revealed a prominence over the left hemisphere. The visual stimuli had an occipital parietal focus whereas the auditory stimuli were parietally centered. These results confirm the importance of the left hemisphere for temporal processing and demonstrate that it is not the result of a hemispatial attentional bias or a peripheral sensory asymmetry.
Publisher: Informa UK Limited
Date: 04-2001
Publisher: Elsevier BV
Date: 04-2009
DOI: 10.1016/J.CORTEX.2007.12.011
Abstract: Visuomotor adaptation to left-shifting prisms can affect performance for a variety of tasks in neurologically intact (normal) participants. This study examined whether visuomotor adaptation affects performance on the greyscales task in normal participants. Forty-two normal participants completed a greyscales task before and after adaptation to either: left-shifting prisms, right-shifting prisms or control spectacles that did not shift the visual scene. Participants demonstrated a leftward bias (i.e., selected the stimulus that was darker on the left as being darker overall) that was reversed by a short period of visuomotor adaptation to left-shifting prisms. In contrast, this bias was unaffected by adaptation to right-shifting prisms and control spectacles. The findings demonstrate that a simple visuomotor task can alter the distribution of spatial attention for the greyscales task in normal participants.
Publisher: Springer Science and Business Media LLC
Date: 02-2004
DOI: 10.1007/S00221-003-1688-X
Abstract: In contrast to unilateral neglect patients, who overattend to the right hemispace, normal participants attend more to the left: a phenomenon known as pseudoneglect. Two experiments examined whether pseudoneglect results from object- or space-based attentional biases. Normal participants ( n=38, 22) made luminance judgments for two left/right mirror-reversed luminance gradients (greyscales task). The relative lateral position of the greyscales stimuli was manipulated so that object- and space-based coordinates were congruent or incongruent. A baseline condition was also included. A leftward bias, found for the baseline condition, was annulled in the incongruent condition, demonstrating an opposition of object- and space-based biases. The leftward bias was reduced in the congruent condition where object- and space-based biases were expected to be additive. This effect was attributed to extraneous factors, which were avoided in the second experiment by presenting the greyscales stimuli sequentially. Once again, no bias was observed in the incongruent condition where object- and space-based biases were opposed. The leftward bias in the congruent condition was the same as the baseline. The results can be explained by a combination of space- and object-based biases or by space-based biases alone and are discussed with reference to a variety of models, which describe the distribution of attention across space.
Start Date: 2015
End Date: 12-2019
Amount: $393,700.00
Funder: Australian Research Council
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End Date: 12-2008
Amount: $195,000.00
Funder: Australian Research Council
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End Date: 12-2013
Amount: $327,500.00
Funder: Australian Research Council
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End Date: 12-2005
Amount: $155,000.00
Funder: Australian Research Council
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End Date: 12-2003
Amount: $10,000.00
Funder: Australian Research Council
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End Date: 12-2014
Amount: $170,000.00
Funder: Australian Research Council
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End Date: 03-2019
Amount: $150,000.00
Funder: Australian Research Council
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End Date: 12-2016
Amount: $360,000.00
Funder: Australian Research Council
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End Date: 12-2021
Amount: $293,015.00
Funder: Australian Research Council
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